* Adding in a new go-agent to use for marketing pipelines. Contains necessary modules to make requirements in edx-mktg

* Setting up the go-agent with a name and resources so it will autoregister with these.

* Leaving php and drush is goagent so we can fall back. Making docs more clear

* Build go-agent-marketing based on tagged image of go-agent

* Attempting to fix build

* Trying latest

* Adding the acquia github key directly into the goagent (#4264)

* Adding the acquia github key directly into the goagent

* Moving the acquia key to the marketing agent

EDUCATOR-1664

This change makes Ansible run, but it has errors

Credentials role was revamped, build a new ame based on that ansible.

A demo site and configuration are now created for credentials sandboxes. This allows developers to provision a sandbox with no additional manual effort.

LEARNER-816

EDUCATOR-1470

LEARNER-1473

This is needed so that we can properly build devstacks without passing in any other config.

Jenkins wasn't updated when this code was changed, so THEME_DIRS
was always null.  We're now going to just set the correct directories
in the internal sandbox config which removes the need for this var
setting here.

This reverts commit afbceb3c.