Blacklist entire directories

[pieterlange]

The blacklist logic currently only matches exact file paths. I'm not sure if this is intentional, but it would be really useful to be able to blacklist entire directories.

Any thoughts on syntax?

blacklisted_file.yaml
blacklisted_dir/

or more explicit:

blacklisted_file.yaml
blacklisted_dir/*

[pieterlange]

With #13 this would mean you'd have to use this for directory blacklisting:

blacklisted_file.yaml
blacklisted_dir/.*

but you could also blacklist file patterns. I figured this would be the more flexible approach.