la4j-0.4.0 release

[Vladimir Kostyukov]

I'm planning to release version 0.4.0 of la4j this summer. There are several issues that I'm going to resolve at this release: https://github.com/vkostyukov/la4j/issues?labels=la4j-0.4.0&state=open. So, if you want to see something special (that is not included yet) in la4j, please let me know by respondnig this thread.