Automatically build code into the jar, package it and publish it on Github releases assets.

[zgypa]

[tttomat19]

#14

[tttomat19]

The release process is triggered by pushing a tag starting with "v". E.g v1.0.0.
Added .jars for core library into release.
Now release looks like this:

[zgypa]

Ok, i'm going to need to look at this and document better. Also we will need to define version schema. I think we should keep below 1 until all DICOM issues are cleared. And there are quite a bit.