Add git options to Source Code section in site navigation editor

Currently SVN is the only type of Source Code repository permitted in the Source Code section of the site navigation editor. Please add the following fields

Label: Browse git
Type: http://
This is the equivalent to ViewVC or Fisheye. It let's the visitor browse the repository using a web browser.

Label: Developer git
Type: ssh (example: git@github.com:arquillian/arquillian.git)
This is the developer's checkout URL, though it's primarily for the project owner. Most developers will fork the project to get read-write access to a repository.

Label: Read-only git
Type: git://
This is the URL passed to git to clone (checkout) the project to pull down the source.

Label: git organization
Type: http://
This is the collection of all git repositories related to a project. It may include sandbox repositories and other related forks.