Removed some completed TODOs
Automated maven central sync

Fixes #136
Migrated to Gradle 2.2.1

Needed for #136 - upgrading versions of build plugins need higher version of Gradle.
Removed not necessary code

The git user is provided via --author tag. No need to configure the user via git config.
Added documentation
Started pushing out the release steps into separate tool
Added the notion of rollback to the release notes operations
Fixed a problem
Added one more rollback operation
Added better description when release process fails
Put back accidentaly removed method
Added a TODO for release process modelling
Promoted most @Incubating features

Removed @Incubating from some internal types as this annotation does not make sense on internal types.

Fixes #137