fix TSLint

[kuzvac]

When TSLint is linting code, he also lints .js files in config folder, and generate "No valid rules have been specified" error.
I we exclude config folder from tsconfig.json file, and error is gone.

From fork-ts-checker-webpack-plugin we can get what files is will be linted. Currently it's all files under src and config folder. Thats because we see error "No valid rules have been specified".
If we exclude config folder from linting, only files under src folder will be linted. And error is gone. :)
For me it's fixed #246

[DorianGrey]

A similar behavior should already be included by the most recent changes to the tslint.json:
78a4fd0

With that change, files from the config folder are explicitly excluded from linting.
This is not yet released, though.

[kuzvac]

Oh yes, i see, thank you.