Make Java SemVer modular

[zafarkhaja]

The idea is to make Java SemVer modular by separating different concepts of SemVer into independent modules using Maven's Project Aggregation. The different modules could be the SemVer's core specification, the SemVer Expressions API, library extensions or there could also be modules of utilities and/or Maven plugins, later on.

This will allow to use only those parts of Java SemVer that are required for a project.

[JamesPoli]

Zafar, It'd be great if you could release an official 1.0.0 version soon; I want to use the library but am worried the API will change. Thanks in advance, Jim