Remote path should be retrieved from VCS where possible

[Sean Hodges]

Some version control systems only have a single remote path for each local copy. Of the current supported VCS' this applies to Subversion, Bazaar, and Mercurial.

For these repositories, it would be useful for the remote path to be retrieved from the VCS client, using a command similar to "bzr info".

Obviously, this technique will not work in the same way for Git, because it can have any number of remote paths being tracked by the same local copy. In this case, it could perhaps default to the commonly used "origin" remote path, with the possibility of over-riding this setting post-configuration.

Additionally, unless an over-ride setting is applied, the remote path should be resolved for every command. This will allow Revisioner to action accordingly when another program changes the remote path being tracked (e.g. "svn switch --relocate").