Allow widget's CSS to be written in Stylus

[Alex Dickson]

Our CSS is all processed by Stylus.

We should let the widgets too. There shouldn't be too much of a hurdle as Stylus is a superset of CSS.

[Iván Loire]

Sounds good. We are rendering CSS now on demand for every widget. I wonder if we can share global variables across all different stylus files..

[Chris Kiehl]

While we are at it we should provide some global variables for common colors that work well together

[Iván Loire]

I spiked a little bit about this yesterday and came with an easy way to define a per theme stylus palette that your <widget>.styl can extend.

[Iván Loire]

This is merged in pre-1.0-release and it would be released (1.0) soon. Widgets written in Stylus have access to Atlassboard's colors palette.