format bugs: not supporting stylus in <style>

[beeplin]

stylus content without {}, : and ; breaks into this after formatting:

[octref]

Similar to #68. There is no formatter for stylus, jade or sass yet. I'll disable formatting for all these regions.

[beeplin]

Another thought:

Anyway it's better to have a formatter than none. Now vetur just format stylus as if it is common css. If the stylus part has {}, : and ; like css, it is formatted perfectly. It doesn't work only if we omit {}, : or ;.

So how about this: Keep it what it behaves now, and in README just mention this trick:?

[beeplin]

coz in most cases we use stylus not because it can save some key presses for {} etc., but because we need to define and use stylus variables.

[octref]

I'll just disable it as most people don't write with {} and ; in stylus.

[octref]

Closing in favor of #82.