Support CVEs from non-git and non-github repositories

[esbena]

The simple data format for benchmark CVEs supports arbitrary revision control systems and hosts, but the only data in there is currently for git repositories that are hosted on github.com.

As a consequence, the implementation currently only supports the git protocol and various github.com related URLs. It would be great to support additional revision control systems (svn, ...), and repository hosts (gitlab, bitbucket, ...), but support should be backed by a few actual CVEs from the wild.