Return full error message for HTTP errors

Non-HeatException, non-remote errors were getting their messages
truncated at the first newline and leaving incomplete error messages the
in json response.  We can only be certain that remote errors raised
through oslo.messaging will conform to the "message + \n + stack_trace"
formula

Closes-Bug: #1358417
Change-Id: I785c6e41101960ea7ceb00c0733c49c2a8aa909f
Fix port residue when instance deletion

A port be implicit-created on ec2 instance creation
if only specify 'SubnetId', so the port id needs to
be stored in instance resource_data so that the port
can be deleted on instance deletion.

Change-Id: I3b685fca26397f8f47d6a732891f06a5360b6487
Closes-bug: #1358581
Merge "Fix port residue when instance deletion"
Merge "Return full error message for HTTP errors"