mld files are not rendered

[dbuenzli]

It seems these files are currently not rendered. That's a problem for my libraries which often have such files.

Also it would be nice to honour the odig convention which allows packages to customize part of the package page landing page via the index.mld file of the package. In my packages these files also have important bits for end-users (see e.g. odig's brr's package page).

[zapashcanon]

@dbuenzli this is now fixed, please open new issues if you find something is wrong with the rendering. :)

[dbuenzli]

Thanks !