Edit any .yml or .properties file using wilfred config

[alvarlagerlof]

Is your feature request related to a problem? Please describe.
I have a bunch of plugins that uses their own config files. Updating multiple files is tedious.

Describe the solution you'd like
I'd be nice to be able to include a relative path to a file in the config command.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.