Now using Travis stages to test, upload artifacts, and publish

.gitignore

@@ -1,10 +1,10 @@
 .gradle
-*/build
+build/
 .DS_Store
 .idea
 spark-warehouse
 *.ipr
 *.iml
 *.iws
 
-isolation-forest/bin
+isolation-forest/bin

.travis.yml

@@ -11,11 +11,32 @@ jdk:
 jobs:
   include:
     - scala: 2.11.8
-      env: SPARK_VERSION=2.3.0 PERFORM_RELEASE=true  # Only one build should have PERFORM_RELEASE=true.
+      env: SPARK_VERSION=2.3.0
+      script: ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION;
     - scala: 2.11.8
-      env: SPARK_VERSION=2.4.3 PERFORM_RELEASE=false
+      env: SPARK_VERSION=2.4.3
+      script: ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION;
     - scala: 2.12.11
-      env: SPARK_VERSION=2.4.3 PERFORM_RELEASE=false
+      env: SPARK_VERSION=2.4.3
+      script: ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION;
+    - stage: upload
+      scala: 2.11.8
+      env: SPARK_VERSION=2.3.0
+      script: ./gradlew bintrayUpload -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION
+      if: (branch = master) AND NOT (type = pull_request)
+    - scala: 2.11.8
+      env: SPARK_VERSION=2.4.3
+      script: ./gradlew bintrayUpload -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION
+      if: (branch = master) AND NOT (type = pull_request)
+    - scala: 2.12.11
+      env: SPARK_VERSION=2.4.3
+      script: ./gradlew bintrayUpload -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION
+      if: (branch = master) AND NOT (type = pull_request)
+    - stage: release
+      scala: 2.11.8
+      env: SPARK_VERSION=2.3.0
+      script: ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION && ./gradlew ciPerformRelease;
+      if: (branch = master) AND NOT (type = pull_request)
 
 # Skipping install step to avoid having Travis run arbitrary './gradlew assemble' task
 # https://docs.travis-ci.com/user/customizing-the-build/#Skipping-the-Installation-Step
@@ -25,15 +46,4 @@ install:
 # Don't build tags
 branches:
   except:
-  - /^v\d/
-
-# Build and perform release (if needed).
-# Currently, only one build is released using Shipkit. Once Shipkit supports releasing multiple builds under the same
-# version, we will automatically publish the artifacts from all builds.
-# https://github.com/mockito/shipkit/issues/858
-script:
-  - if [ $PERFORM_RELEASE == true ]; then
-      ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION && ./gradlew ciPerformRelease;
-    else
-      ./gradlew build -s -PscalaVersion=$TRAVIS_SCALA_VERSION -PsparkVersion=$SPARK_VERSION;
-    fi
+    - /^v\d/