chore: version bump

feat: version bump, updated gradle and added some docs for new methods

fix: use new lifecycle runtime dependency

fix #18: updated recycler view to 1.2.0. Deprecated older declarative…

… extensions. Implemented Maven Central publishing. Dropped Bintray.

version bump to 3.1.2

feat: renderable items now also accepts nullable stuff

feat: refactor layout names

feat: enhanced release script

Updated bintray plugin and using gradle maven plugin publication to d…

…eploy on bintray

- Updated Gradle Plugin to 3.4.1

- Updated Gradle to 5.4.1
- Using new Sky-UK Gradle maven plugin and dropped dcendents maven plugin
- Implemented "prepareForReuse" in view holders
- Added additional declarative extensions