This changes the init target to be idempotent: most importantly it will now
never overwrite a Makefile if it exists. Additionally 'make init' will
generate the .vimrc files. Yay, no more stupid 'added fairies' commits! ;)
Ditch the building of an archive (.a) in favour of linking all objects in a
directory into a lib.o file. This makes it easy to link in subdirectories
and more importantly keeps the build logic in the local subdirectories.
Note: after updating you will have to rm **/*.a if you do not make clean
before updating.