Sync toci with current devtest

Toci hasn't worked in nearly two weeks, ever since some stuff was refactored,
after this commit toci
1. is now back in sync with devtest in incubator.
2. brings up an overcloud by default (set TOCI_DO_OVERCLOUD=0 to stop a
   undercloud).
3. clones all git repositories to /opt/toci (these arn't refreshed
   between toci runs unless removed).
4. changes some env variables so that the default behaviour is now
   closer to a what a user setting up a dev env would want.
5. removes unused patches and adds some new ones.
6. Adds a bit more documentation.

Change-Id: I19a34b1a400ec646f37310f265d1345bb6882dc3