Fix a few glitches for the Javascript conversion of tabular diffs to unified diffs.
Fix a few glitches for the Javascript conversion of tabular diffs to unified diffs.

Those diffs, once copy/pasted, wouldn't apply for a couple of reasons:
 - extra "File " prefix in file indicator line
 - extra "," in chunk index line
 - extra leading space in each chunk line
 - extra trailing non-breaking space in each chunk line


git-svn-id: 0d96b0c1a6983ccc08b3732614f4d6bfcf9cbb42@6853 af82e41b-90c4-0310-8c96-b1721e28e2e2

rbaumg/trac,rbaumg/trac,rbaumg/trac,rbaumg/trac