Route53 querying and updating logic

Implementation of the Route53 querying and updating logic. The application
supports both IPv4 and IPv6, as well distinct RecordSets for each. The
configuration is loading from a YAML file.

.gitignore

@@ -1,2 +1,4 @@
 /target
 /*.csv
+/*.yml
+.swp

.vscode/launch.json

@@ -0,0 +1,45 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug executable 'rust-aws-ddns'",
+            "cargo": {
+                "args": [
+                    "build",
+                    "--bin=rust-aws-ddns",
+                    "--package=rust-aws-ddns"
+                ],
+                "filter": {
+                    "name": "rust-aws-ddns",
+                    "kind": "bin"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
+        },
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug unit tests in executable 'rust-aws-ddns'",
+            "cargo": {
+                "args": [
+                    "test",
+                    "--no-run",
+                    "--bin=rust-aws-ddns",
+                    "--package=rust-aws-ddns"
+                ],
+                "filter": {
+                    "name": "rust-aws-ddns",
+                    "kind": "bin"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
+        }
+    ]
+}