travis caching optimisation

Author: simplesteph

.travis.yml

@@ -1,5 +1,6 @@
 language: scala
 sudo: required
+jdk: oraclejdk8
 
 services:
   - docker
@@ -21,7 +22,13 @@ deploy:
 #    condition: "foo == bar && baz==bat"
 #    repo: simplesteph/kafka-security-manager
 
+
+before_cache:
+  # Tricks to avoid unnecessary cache updates
+  - find $HOME/.sbt -name "*.lock" | xargs rm
+  - find $HOME/.ivy2 -name "ivydata-*.properties" | xargs rm
+
 cache:
   directories:
-  - $HOME/.ivy2
+  - $HOME/.ivy2/cache
   - $HOME/.sbt