twbs/bootstrap-sass — pull request #737 by parhumm (2014-10-08 13:04:10+00:00)
Title: Add RTL Support to Bootstrap Sass

I use https://github.com/parhumm/Sass-Direction-Controller to add RTL and LTR Support for bootstrap.
I don't know how do 'guidelines for contributing', but it can help bootstrap to be RTL Support.