add LaTeX rendering for file viewer

[motorcityadam]

This functionality already seems to be implemented in the Wiki pages of OSF, but I feel that OSF file rendering would be equally beneficial. Please review my report below. Thank you for your consideration.

Steps

1. Go to a Project component.
2. Go to the Files tab.
3. Add a LaTeX (.tex) document to the OSF store.
4. View the file (with selected the "View" tab).
5. The contents of the file appear as seen in the screenshot attached.

Expected

This is more a desired feature than an expected feature.

The LaTeX statements should be rendered when the "View" tab is selected.

Actual

The file does not render at all (both MathJax and plain LaTeX statements are provided in the example file).

Possible Cause

Functionality not implemented.

Environment

Tested on OS X 10.10.5 using Chrome 48.0.2564.97

[GaryKriebel]

Thanks @adamjcook!

@sloria, who should review the code?

[sloria]

AFAIK, LateX rendering has not yet implemented. This would need to be implemented into MFR, so @felliott would be the one to review.

[GaryKriebel]

@felliott .... is LaTeX in MFR now?