Split homepage, scm and repo links

[jayvdb]

For GitHub, GitLab, and many others, the scm and repo link are the same.

However even for GitHub, the homepage is often different, being a RTD or Github Pages site.

For sourceforge (and BitBucket until June?), they support multiple VCS so the type of VCS and link are important to interact with the repo. This info can be gleaned from the info processed while finding the SCM, but validating that may be more trouble than using a specialised library. This library can at least indicate that the link is only useful for the SCM, and describe which SCM is used by the project.

The most important aspect however is the results which are a webpage, and no SCM can be found, such as pychart. Many tools like rpm spec builders (upt, py2pack, etc) are looking for a homepage only.

Another cohort is trac, which is an SCM, but the code repository isnt readily available.

Also launchpad is often used only as SCM/bug tracker, but isnt being used the code repo.

[jayvdb]

Also multiple SCMs/bug trackers/etc, like #41