Cache dependencies during build

[milanmajchrak]

We wanted to decrease build time - successful.
Then jm wanted to not build every time to prevent (probably) dependency injection.
Doesn't appear to be entirely possible.

there is ADD . - meaning every push requires new build (every push contains SOME change to files,
which results in new build)

maybe he needs no sources, just POMs, check it

this is now done for security reasons only, it would not be saving any time

Uses mvn package. Is this really dependencies then?

I suggest dropping this one. It is wrong naming, not really a dependencies.
I strongly believe this is not essential to our effort in the current moment.