Add SASS support documentation #1007#1008

Merged

gaearon merged 7 commits intofacebook:masterfrom

tsironis:sass-support-docs

Feb 12, 2017

Commits on Nov 4, 2016

Commits on Nov 6, 2016

Chain build-css with watch-css script, fix typos
tsironis
authored

Commits on Nov 10, 2016

Update Sass and Less naming style
tsironis
authored

Commits on Nov 21, 2016

Fix wording, remove offensive words
tsironis
authored

Commits on Feb 12, 2017

Slightly rewite
gaearon
authored