Added documentation, fixed Checkstyle Violations
* added missing javadoc
* fixed some checkstyle violations
ISSUE #38: FIXED
* added caching
ISSUE #39: FIXED
* added caching to factory
Fixed Builder
* fixed some tests
Added Distribution
* added assembly to add all version for the user into one zip
Added Contributing and Readme
* added general contributing rules
* added general project information
* added contribution workflow
Ignore Gimp Binary Files
* added *.xcf to gitignore
Implemented API Changes