Use Github Markup library instead of Markdown parser

[stevestreza]

My repository, stevestreza/Relayout, uses a reStructuredText file for its README. ReadmeScore currently is unable to assign a rank to my project because of this, even though rst is a valid README format for GitHub.

The README detection looks to be completely dependent on README files being in the Markdown format. But GitHub supports a variety of formats for README files, including reStructuredText. They also have published a Ruby library that handles converting README files in a variety of formats to HTML.

Since ReadmeScore relies on HTML parsing, not anything specific to Markdown, I would love to see the library changed to support the variety of file formats that GitHub supports, rather than the one used only by a limited subset of repositories.

Thank you!

[clayallsopp]

hey @stevestreza - I don't have the bandwidth to make those changes myself, but would happily merge any PR that does!

[stevestreza]

No worries, thank you for the response!