Path globs support

[ghost]

Hello,
I'd like to ask you to implement support for specifying input files by globs. That would allow us to run htmlcs from build (e.g. npm) scripts in a portable (cross-platform) way. There is actually a lot of linters that accept globs already. They use minimatch AFAIK. I mean some module based on it like globby, glob-all, globule or simple-glob.

[chriswong]

We do this work in fecs：

$ fecs check *.html