Tyrannical now use awful.rules for more callbacks. It can be
better integrated, but that's enough for this commit.
This commit also drop the legacy and request sub-module, as the
legacy was dead code anyway amd requests are now mandatory.
It is now possible to spawn with an array of properties, see the README.md
for more details. It require Awesome 3.5.3+, some patch will get into 3.5.6
to make this even better. I also added the 'new_tag' property to be used
with spawn.
* Also fix issue #37, sorry about that one...