Ensure cm-api is ready before start cm-alarm

The patch ensure that ceilometer-api is ready before
starting the ceilometer-alarm-evaluator service.

This ensure that ceilometer-alarm-evaluator doesn't log a error message
on startup due to not yet available ceilometer-api.

Closes bug: #1243249

Change-Id: Icff3e972ec485f26c014071f68079593a14b7240
git-ignore files generated by "./tools/build_docs.sh ."

Change-Id: Ibf190998e52e7814ddc7f7ab4cf174aee28df9bf
zsh openrc compatibility

Replacing $BASH_SOURCE with ${BASH_SOURCE:-$0} makes devstack zsh friendly: in
bash, $BASH_SOURCE is used per usual; in zsh, where $BASH_SOURCE isn't
defined, $0 is used, which, unlike in bash, evaluates to the current
source file.

Now you can source devstack's openrc from a zsh shell.

Tested with bash and zsh from directories other than the root devstack
directory.

Change-Id: Iab1a817b15d86144163b5094bb58f94b15c598a0
Merge "Ensure cm-api is ready before start cm-alarm"
Merge "zsh openrc compatibility"
Merge "git-ignore files generated by "./tools/build_docs.sh .""