stylefmt ignore .stylelintrc.json

[azu]

Hi, Nice work for supporting stylelint configuration #61

I've noticed unexpected behavior that stylefmt ignore .stylelintrc.json(.stylelintrc.<ext> pattern).

• https://github.com/morishitter/stylefmt/blob/ede1ed3b1a1c7b7a849849c57da77029d8c7dd83/lib/params.js#L15 (rc-loader can't load .stylelintrc.<ext>.

stylelint can load config from .stylelintrc, .stylelintrc.json, .stylelintrc.yaml, .stylelintrc.js, .stylelintrc.config.js and a stylelint property in package.json.
Available file naming/format is defeined in cosmiconfig.

It is better that adding note like "only support .stylelintrc file (without extension)" to README, I think.

[matype]

@azu Thank you for telling me. I will fix it using cosmiconfig.

[matype]

@azu Just released v3.1.0 that introduced cosmiconfig to load the configuration file in the same way as stylelint. Please confirm it :)

[azu]

Work fine. Thanks