Don't run the chef-webui on SUSE by default
install-chef-suse: introduce $BARCLAMP_SRC

Allows specifying a directory from which the barclamps are being installed.
Defaults to /opt/dell/barclamps/. Overriding that can be useful when
CROWBAR_TESTING=true to install from a git checkout.
install-chef-suse: Rework CROWBAR_TESTING mode a bit

- Don't verify repo md5 sums in CROWBAR_TESTING mode, they are changing too
  often during development
- install more rubygem dependencies
- disable the addtional IBS repos for now. Needs to be reworked if needed at
  all, added a clarifying comment to that
- updated docs
Merge pull request #1801 from rhafer/master

more install-chef-suse.sh changes for pebbles