Fix for using upload.py with bazaar based on #14053

[muffinresearch]

This is the explanation for the differences between this and #14053

http://codereview.appspot.com/17053/diff/1/2
File upload.py (right):

http://codereview.appspot.com/17053/diff/1/2#newcode188
Line 188: account_type = "HOSTED"
This change is to make upload.py work for both codereview.appspot.com as well as
hosted instances.

http://codereview.appspot.com/17053/diff/1/2#newcode1197
Line 1197: filename = os.path.join(self.repo_dir, filename)
This is to make the bazaar integration work at any level of the branch.

http://codereview.appspot.com/17053/diff/1/2#newcode1307
Line 1307: # bzr info will return an exit code of 0 if you're in a branch
This differs from #14053 in that it uses "bzr root" to work out the base path to
the branch. This means diffs can be generated at any level

[muffinresearch]

Patch Set 3 is a better review as it's a diff on #14053. I've also made a
correction for an issue where bzr root returns within an svn checkout.

See: http://codereview.appspot.com/17053/diff/6/1003