Go back to using go build tags instead of moving files around

* cherry-picked from new_work_rebase
  commit 7f856727e70d597045791b318c40621a4c27c26e

Conflicts:
	sound/silent_manager.go.disabled
This is going to depend upon the runningwild/golua work

* This gets things a bit further (not much though) and causes the Lua
  scripts to actually work.

* Ported from new_work_rebase
  commit cdaaed8b8b4669be366c122a24f977a7d04321b6