improve scriptability of post-commit

Review Request #212 — Created Jan. 25, 2008 and discarded — Latest diff uploaded


Review Board SVN (deprecated)


 * post_review separated from __main__ to allow importing from other scripts such as post-commit hook; allows any command-line option to be set programatically in call to post_review method 
 * adds --submit-as option
 * adds --repository option; allows empty basedir for repo diffs
 * includes json responses in debug mode
 * consolidates .reviewboardrc loading into one place in __main__
 * allow use of -c (--revision) with svn and removed -c as a weird special case in parse_options; removed --revision-range: reviewing multiple revisions in svn makes as little sense as in p4
 * generalizes and expands request field setting in mutable_request_fields
 * allows any (long-form) command-line option to be set in .reviewboardrc (backwards incompatibility: this means "REVIEWBOARD_URL" in .reviewboardrc should now be just "server"); if also specified on command-line, command-line takes precedence

I've included this as a diff against post-review but the name needs to be changed to make it importable (hyphens are not legal in a module name).  I used the obvious ""