add tile/stack comment. fix not ended string
add require line
remove debug info
current-policy is now a fun-box instead of a parameter.

It can now be changed directly from the client, like a hotfix.
update readme for tiling/stacking
add comments
comments + fix version number
fix rwind restart.

The problem was that set-input-focus was called after exit-display, so the connection to the X server was lost. This resulted in strange errors about xcb complaining either about XInitThreads not being called or the event queue not being empty.