Add support for additional mime-types.

[nojaf]

Fixes #749.

[baronfel]

This is a good escape hatch, but should the default set of MIME times be expanded? .mp4 is pretty common these days.

For reference, here is the set of file-extension-based MIME types that AspNetCore knows out of the box today. I think it would be nice to have common extensions like these Just Work ™️

[nojaf]

Perhaps, but that begs the question should it be done here or in Suave itself?

[baronfel]

I think it could be a two-pronged approach - fix here as an intermediate, and provide the same fix upstream to Suave to let them decide if they want to take it.

[nojaf]

Sounds reasonable, I would need the escape hatch for the more obscure stuff in my project.

[nojaf]

@dsyme
, @eiriktsarpalis how do you want to see this fixed?

[dsyme]

how do you want to see this fixed?

I think expanding the list here to include all the entries from ASP.NET Core makes sense, and then also contributing that to Suave.

[dsyme]

@nojaf The rest of this PR is fine. The one thing is that I don't really know if there are standard command line flags on web servers for this sort of thing - if there is we should follow that standard for the name of the flag - if not what you have is fine.

[nojaf]

Closing in favour of #752.