heat_keystoneclient don't pass project and trust_id

When creating a keystoneclient connection with a trust, we should
not pass the project_name, as the token can only be scoped to either
a trust or project, not both.  Previous versions of keystoneclient
worked with both, but recent changes mean this no longer works.

Change-Id: I5c7e7498137d428360f2b5f1e8bd2d079c80cd9b
Closes-Bug: #1288223
Merge "heat_keystoneclient don't pass project and trust_id"