Redmine

I have some repositories that are configured with SVNPath instead
of SVNParentPath (I'm doing it to be able to use additional
authentication methods them, see issue #6414).

With the current Redmine.pm code (1.0.1) the authentication against
Redmine fails because the project_id is not guessed as it should
(the apache Location points to the repository, not to it's parent
path).

To solve the problem I've patched Redmine.pm to allow the use of a
new option that adjusts the project_id to use; if the option is set
the get_project_identifier function returns that name instead of
calculating it from the URI and the apache location).

The attached patch is against an export of the redmine-1.0.1 tag.