All: Replace Release.project with more appropriate values

Use package name for CDN. Use bugs and repository fields for changelog.
Adds a _packageUrl method that the Trac module can also use.

Fixes gh-49
Closes gh-52

#50 and #51 were side effects while working on this. I actually missed the change from #50 a few times, since I put that in a separate branch.

Tested this against fake-project, jquery, jquery-ui, jquery-mobile and qunit. Since the changelog generation is barely working, I specifically check the return value of `_ticketUrl` and `_repositoryUrl` for each.