GitLab

* function for pod resolution with error handling already done (guaranteeResolvePod)
* function for replacements with error handling already done (guaranteeCachedReplacements)
* separate comand-exec endpoint (currently a get, should be post?)

callback -> promises
always return request with result in the body attributes

analytics-toolkit beaker still using old /notebook-edit entrypoint

* better handling of failures
* entry point fixes