Merge: contrib: generate Makefiles with nitpackage

I applied `nitpackage --gen-makefile` (#2662) on contrib:
* generated Makefile for projects without any (76a17aa)
* replaced some existing Makefiles with their generated counterpart (a95be1e)
* manually merged generated rules into existing Makefiles (3b85ec3)

Please consider only these commits as the rest of them belongs to another PRs.

Pull-Request: #2685