Revert "Makefile rewritten to support multiple sources"

This reverts commit b876e19dbdd49cee96a78b0c02df8c713c8d40cf.
Revert "remove non-default platform makefiles"

This reverts commit e69008555bdda93ae6e3117b2562df34578d24b1.
Move key binding definitions into cfg.h
Implemented key bindings behavior.
NB i3wm doesn't support _NET_WM_DESKTOP window property. So desktop switching doesn't work with that yet