Source functions from stackrc

stackrc now requires GITREPO, GITBRANCH, GITDIR and has been
dependent on functions for a while (is_package_installed).  Ensure
we source the required functions file when stackrc is loaded.  Avoids
unexpected issues in grenade where they may or may not have been loaded
depending on the configuration.

Closes-bug: #1377274

Change-Id: I5027cfad07af0de7ff39f424601d6f7ec5dcadae
Refactor swift config services

Make the sed the command to change the recon_cache_path into the renamed
generate_swift_config_services

Change-Id: I6092c26836320fab607eb9cd07f63189a9ba1ddd
Merge "Refactor swift config services"
Merge "Source functions from stackrc"