[Feature] Add support to load settings from a specific file too.

[JoseGalRe]

Hi, like title, add a way to use a custom file to load settings.

like: todohighlight.json, todohighlight.rc, todohighlight.js ...etc, in the root path.

always should have support for settings.json

This way the user will have 2 options, custom file and vscode configuration to load the configuration.