Preserve double slashes in the scm connection url - identifies absolute repository paths for mercurial

The mercurial scm (hg) use double slashes after the hostname part of the repository url to identify that a repository path is absolute, as opposed to relative. Maven should not remove such double slashes from the scm connection url.

The following is an example of a absolute repository path: scm:hg:ssh://localhost//opt/foo. Note the double slash between 'localhost' and 'opt', it is interpreted by hg as the absolute path /opt/foo on the server localhost.

A relative repository url on the other hand, scm:hg:ssh://localhost/foo, is resolved relative to the user's home directory on the server localhost, f.x /home/user/foo.

With maven 3.0 and 3.0.1 double slashes are silently removed and it is thus not possible to release a project that use a absolute scm connection url with mercurial.

The provide patch removes the removal of double slashes from the url normalizer. It also change the test case for the removal code to test that url:s that contain double slashes are preserved instead.