This is was over complicating things and there can be only one banan-os build at a given time.
Fix some bugs and add pkg-config for the port system. Also ncurses is now downloaded from the gnu mirror in the hope that it works better
Now ports define some environment variables, and call a unified bash script that handles configuration, recompilation and installation. If a port uses non-configure buildsystem, port script can also specify custom build and install step.