Fix posting with perforce paths.
Review Request #7306 — Created May 17, 2015 and submitted
When passing in a path argument to 'rbt post' instead of a revision, we'd crash
inside the guessing code. I've changed the assertion to a conditional in order
to fix this.
Ran unit tests.
Tool: Pyflakes Processed Files: rbtools/commands/post.py Tool: PEP8 Style Checker Processed Files: rbtools/commands/post.py