Changes

Expose Runner Status API
Update build.gradle
- Updated to latest snapshot version presented in pom.xml
- Use latest patch version of jackson library
- Updated to latest Gradle plugins syntax
- Updated Gradle Wrapper to 4.4
Added more generated files/directories to .gitignore
Updated pom.xml
- Updated to version 0.23.0 of fabric8's maven plugin to run integration test locally
- Updated source/target compatibility to Java8
Addressed potential bug of returning nullable Boolean as primitive boolean.

timols / java-gitlab-api