Patch Anchoring: UI Improvements for uploading patches

Uploading of patches automatically tries to anchor the patch.
For patches with ambiguous file names, uploading against a server with many large complicated SVN repos, this anchoring can take a long time.
We should:

• Set a limit on the amount of time we try to anchor the patch
• Limit paths we automatically anchor to to the "trunk", for SVN (this may/may not be possible)
• Differentiate for the user between uploading the patch and anchoring
  If this fails or times out, we should:
• Go straight to allowing the user to pick a repository and path to anchor to.