Feature request: A viewer for R Markdown Notebooks

Problem to solve

Currently R Markdown documents or R notebooks (both .Rmd files) are rendered as plain text. If it would be possible to have them rendered as HTML, it is easier to view the content and share/collaborate on it.

Further details

At the moment Github creates a better view for Rmd files: https://github.com/jjallaire/deep-learning-with-r-notebooks/blob/master/notebooks/2.1-a-first-look-at-a-neural-network.Rmd

Proposal

Since a year ago it is possible to view Jupyter notebooks: https://gitlab.com/gitlab-org/gitlab-ce/issues/2508 A similar approach can maybe be used to implement a viewer for R Markdown files.

What does success look like, and how can we measure that?

For example, this R Markdown document (https://gitlab.com/marekpetrik/ML-Spring2018/blob/master/notebooks/class1/introduction.Rmd) is rendered as plain text on gitlab.com, where the HTML rendered version (http://www.cs.unh.edu/~mpetrik/teaching/intro_ml_17_files/introduction.html), is much more readable.