Enable jump to file on abbreviated @import

For the stylus:

```
@import layout
```

If you do `gf` on `layout` it should automatically check for (and 
jump to) `layout.styl`
Merge pull request #30 from benjie/patch-1

Enable jump to file on abbreviated @import
Fix syntax highlighting for stylus import/require
add; example of require fix
Release 0.9.0
Make installs slightly easier

I love when I hit a vim plugin and I can copy & paste the commands. This change just makes it a little easier for people to install.
Merge pull request #35 from dbryand/patch-1

Make installs slightly easier
add; pointer events highlighting
trailing spaces removed
css property user-select added
user-select related test
Merge pull request #37 from gmunkhbaatarmn/master

Missing property: user-select
improve cssDefineBlock: do not contain stylusImportList (rel #34)
use contains=TOP instead of excluding stylusImportList
Merge pull request #39 from itchyny/master

improve cssDefineBlock: do not contain stylusImportList (rel #34)
Release 0.9.1