diff --git a/package-lock.json b/package-lock.json
index 8628849..3ffe4a9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,7 +9,7 @@
       "resolved": "https://registry.npmjs.org/array-union/-/array-union-1.0.2.tgz",
       "integrity": "sha1-mjRBDk9OPaI96jdb5b5w8kd47Dk=",
       "requires": {
-        "array-uniq": "1.0.3"
+        "array-uniq": "^1.0.1"
       }
     },
     "array-uniq": {
@@ -23,19 +23,9 @@
       "integrity": "sha1-iYUI2iIm84DfkEcoRWhJwVAaSw0="
     },
     "async": {
-      "version": "2.6.1",
-      "resolved": "https://registry.npmjs.org/async/-/async-2.6.1.tgz",
-      "integrity": "sha512-fNEiL2+AZt6AlAw/29Cr0UDe4sRAHCpEHh54WMz+Bb7QfNcFw4h3loofyJpLeQs4Yx7yuqu/2dLgM5hKOs6HlQ==",
-      "requires": {
-        "lodash": "4.17.11"
-      },
-      "dependencies": {
-        "lodash": {
-          "version": "4.17.11",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz",
-          "integrity": "sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg=="
-        }
-      }
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/async/-/async-3.2.0.tgz",
+      "integrity": "sha512-TR2mEZFVOj2pLStYxLht7TyfuRzaydfpxr3k9RpHIzMgw7A64dzsdqCxH1WJyQdoe8T10nDXd9wnEigmiuHIZw=="
     },
     "balanced-match": {
       "version": "1.0.0",
@@ -52,7 +42,7 @@
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
       "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
       "requires": {
-        "balanced-match": "1.0.0",
+        "balanced-match": "^1.0.0",
         "concat-map": "0.0.1"
       }
     },
@@ -66,13 +56,13 @@
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       "integrity": "sha1-wSyYHQZ4RshLyvhiz/kw2Qf/0ag=",
       "requires": {
-        "globby": "5.0.0",
-        "is-path-cwd": "1.0.0",
-        "is-path-in-cwd": "1.0.1",
-        "object-assign": "4.1.1",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1",
-        "rimraf": "2.6.3"
+        "globby": "^5.0.0",
+        "is-path-cwd": "^1.0.0",
+        "is-path-in-cwd": "^1.0.0",
+        "object-assign": "^4.0.1",
+        "pify": "^2.0.0",
+        "pinkie-promise": "^2.0.0",
+        "rimraf": "^2.2.8"
       }
     },
     "fluent-ffmpeg": {
@@ -80,8 +70,8 @@
       "resolved": "https://registry.npmjs.org/fluent-ffmpeg/-/fluent-ffmpeg-2.1.0.tgz",
       "integrity": "sha1-5quF51uo5JEZo5AM2d8Q05gx05I=",
       "requires": {
-        "async": "2.6.1",
-        "which": "1.3.1"
+        "async": ">=0.2.9",
+        "which": "^1.1.1"
       }
     },
     "fs.realpath": {
@@ -94,12 +84,12 @@
       "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.3.tgz",
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       "requires": {
-        "fs.realpath": "1.0.0",
-        "inflight": "1.0.6",
-        "inherits": "2.0.3",
-        "minimatch": "3.0.4",
-        "once": "1.4.0",
-        "path-is-absolute": "1.0.1"
+        "fs.realpath": "^1.0.0",
+        "inflight": "^1.0.4",
+        "inherits": "2",
+        "minimatch": "^3.0.4",
+        "once": "^1.3.0",
+        "path-is-absolute": "^1.0.0"
       }
     },
     "globby": {
@@ -107,12 +97,12 @@
       "resolved": "https://registry.npmjs.org/globby/-/globby-5.0.0.tgz",
       "integrity": "sha1-69hGZ8oNuzMLmbz8aOrCvFQ3Dg0=",
       "requires": {
-        "array-union": "1.0.2",
-        "arrify": "1.0.1",
-        "glob": "7.1.3",
-        "object-assign": "4.1.1",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1"
+        "array-union": "^1.0.1",
+        "arrify": "^1.0.0",
+        "glob": "^7.0.3",
+        "object-assign": "^4.0.1",
+        "pify": "^2.0.0",
+        "pinkie-promise": "^2.0.0"
       }
     },
     "inflight": {
@@ -120,8 +110,8 @@
       "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
       "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
       "requires": {
-        "once": "1.4.0",
-        "wrappy": "1.0.2"
+        "once": "^1.3.0",
+        "wrappy": "1"
       }
     },
     "inherits": {
@@ -139,7 +129,7 @@
       "resolved": "https://registry.npmjs.org/is-path-in-cwd/-/is-path-in-cwd-1.0.1.tgz",
       "integrity": "sha512-FjV1RTW48E7CWM7eE/J2NJvAEEVektecDBVBE5Hh3nM1Jd0kvhHtX68Pr3xsDf857xt3Y4AkwVULK1Vku62aaQ==",
       "requires": {
-        "is-path-inside": "1.0.1"
+        "is-path-inside": "^1.0.0"
       }
     },
     "is-path-inside": {
@@ -147,7 +137,7 @@
       "resolved": "https://registry.npmjs.org/is-path-inside/-/is-path-inside-1.0.1.tgz",
       "integrity": "sha1-jvW33lBDej/cprToZe96pVy0gDY=",
       "requires": {
-        "path-is-inside": "1.0.2"
+        "path-is-inside": "^1.0.1"
       }
     },
     "isexe": {
@@ -156,16 +146,16 @@
       "integrity": "sha1-6PvzdNxVb/iUehDcsFctYz8s+hA="
     },
     "lodash": {
-      "version": "4.17.11",
-      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz",
-      "integrity": "sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg=="
+      "version": "4.17.21",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
     },
     "minimatch": {
       "version": "3.0.4",
       "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
       "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
       "requires": {
-        "brace-expansion": "1.1.11"
+        "brace-expansion": "^1.1.7"
       }
     },
     "moment": {
@@ -183,7 +173,7 @@
       "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
       "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
       "requires": {
-        "wrappy": "1.0.2"
+        "wrappy": "1"
       }
     },
     "path-is-absolute": {
@@ -211,7 +201,7 @@
       "resolved": "https://registry.npmjs.org/pinkie-promise/-/pinkie-promise-2.0.1.tgz",
       "integrity": "sha1-ITXW36ejWMBprJsXh3YogihFD/o=",
       "requires": {
-        "pinkie": "2.0.4"
+        "pinkie": "^2.0.0"
       }
     },
     "rimraf": {
@@ -219,7 +209,7 @@
       "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.3.tgz",
       "integrity": "sha512-mwqeW5XsA2qAejG46gYdENaxXjx9onRNCfn7L0duuP4hCuTIi/QO7PDK07KJfp1d+izWPrzEJDcSqBa0OZQriA==",
       "requires": {
-        "glob": "7.1.3"
+        "glob": "^7.1.3"
       }
     },
     "which": {
@@ -227,7 +217,7 @@
       "resolved": "https://registry.npmjs.org/which/-/which-1.3.1.tgz",
       "integrity": "sha512-HxJdYWq1MTIQbJ3nw0cqssHoTNU267KlrDuGZ1WYlxDStUtKUhOaJmh112/TZmHxxUfuJqPXSOm7tDyas0OSIQ==",
       "requires": {
-        "isexe": "2.0.0"
+        "isexe": "^2.0.0"
       }
     },
     "wrappy": {
diff --git a/package.json b/package.json
index aad883e..3b2185a 100644
--- a/package.json
+++ b/package.json
@@ -43,10 +43,11 @@
     "sinon-chai": "2.9.0"
   },
   "dependencies": {
+    "async": "^3.2.0",
     "bluebird": "3.5.0",
     "del": "2.2.2",
     "fluent-ffmpeg": "2.1.0",
-    "lodash": "^4.17.11",
+    "lodash": "^4.17.21",
     "moment": "2.22.2"
   }
 }