upstream miscellaneous commits from essex-hack-suse

This pull request contains a large chunk of the remaining commits to be upstreamed from essex-hack-suse to release/pebbles/master.  It is a miscellaneous collection of fixes which are mostly SUSE-specific (e.g. affecting the AutoYaST process or Apache setup).  Changes which affect all OS include:

* moving logs into `/var/log/crowbar` and `/var/log/crowbar/crowbar-join` to avoid cluttering `/var/log`
* enhancement for managing SSH authorized keys
* a state machine tweak which seems to have been previously missed from backporting from trunk to Pebbles (see 740fced9bf)
* defensive fix against `$HOSTNAME` not being set
* `provisioner` recipe requires `utils`

Not yet tested on Ubuntu - will do soon.