pick one of the valid config files

[thefourtheye]

ESLint supports more than one way to specify the configuration files. The valid list of files can be seen here http://eslint.org/docs/user-guide/configuring#configuration-file-formats This patch checks if any of those files exist and if it does return that file name, otherwise return .eslintrc as the default value.

Fixes: #12

[silverwind]

Nice work. I think a similar patch might be in order for the regular ESLint plugin, throught I'm not exactly sure how the configuration gets loaded there.

[AviDuda]

I need this. 👍 @roadhump, any news about merging this in?

[silverwind]

ping!