Currently some mistral errors are masked in the cli with non helpful messages
like:
ERROR (app) Bad Request (HTTP 400)
That is due to ResourceManagers not using the standard underscore
methods defined in the base class. Those underscore methods have the
appropriate try catch to parse the unfriendly keystoneauth errors into
more cli friendly errors like:
ERROR (app) Invalid input [name=std.echo, class=mistral.actions.std_actions.EchoAction, missing=['output']]
This adds the try catch to the non standard methods and change the
action_execution.create to use the standard method
Change-Id: I2573cb093e97ce378fc1d255d8b38e2ce818c8e5
Closes-bug: #1754093
3f0255f416