cleanup: clean up and simplify the build system

cleanup: clean up and simplify the build system

Mainly: Nothing is built in the generic/ subdirectory any more now:
global stuff is built in global/
local stuff is built in local/
libraries are no longer renamed with _local or _global prefixes.

This is another step heading towards proper modularization - and
installing each module on its own, for both local and global
tools.

Signed-off-by: Gordon Hecker <gh@emlix.com>