Setup gradle build

Add `license` plugin and apply ASL 2.0 to all sources
Add `publishing` and i`bintray` plugins with custom pom settings
Add `cobertura` and `coveralls` plugins
Merge pull request #4 from jbovet/master

Thanks, I'll just tweak the assertion with a little regex so it doesn't fail on each build increment.
Add regex to api version endpoint spec.
Merge branch 'build_setup_update' of https://github.com/aalmiray/gvm-sdk into aalmiray-build_setup_update

Conflicts:
	LICENSE
	build.gradle
Minor code formatting.
Set version to 0.5.2
Set bintray username and password to invalid if not provided