migrate to single-module build
Nebula Build - Single Module
Merge pull request #1644 from benjchristensen/nebula-build

Nebula Build - Single Module
Update build.gradle

GroupID is not needed as it will use the default `io.reactivex`
Create .travis.yml
JDKs for Travis
Only JDK 7 for Travis
Travis build image
Remove ParallelMerge

Removing confusing operator before locked in stone with 1.0.0 Final
Merge pull request #1645 from benjchristensen/remove-parallel-merge

Remove ParallelMerge