Updated gradle plugin
Updated build tools/target sdk
Use identical path for default timezone

It was using the ID string, which is almost identical to what DateTimeZone does
internally when it first tries to convert TimeZone -> DateTimeZone; but now it
literally does the exact same code, which is a bit safer, I guess.
Updated to tzdata 2014j
Bumped to 2.5.1 r9
Updated gradle-mvn-push plugin
Fixed issues with javadoc
Merge branch 'dev'