Makefile/Installation improvements

Introduce compile-time variables (dynamic $LIB!) by injecting variables into the executable usin metaprogramming

Fix some bad style: Do not use sudo in Makefiles, rather invoke the makefile with root privileges. This serves to avoid confusion and permission-scrambeling if installation without  higher permissions is required.

Avoid using scp as it might not be installed everywhere. (Also: What's wrong about good old cp?).

Do not use git/refs/origin for the github target as this can scramble settings for devs who work on forks.