Config file

[edi9999]

It would be great to have a way to customize icdiff from a file, for example, located in :

~/.icdiffrc

or :

~/.icdiff.conf

For example, I would like to set the following color map as default for all my scripts :

--color-map=subtract:red_bold,description:blue_bold

[jeffkaufman]

If you or someone else wanted to write a PR for this I'd be happy to review!