Nested .gitignores

[kpwelsh]

It would be great if this library had support for layering .gitignores to handle cases like the following:

package/
  .gitignore
  my_package/
    resources/
      .gitignore

I was working with a repo that has, a perhaps ill advised, gitignore like the following:

Root:

*.rst

Somewhere deep in the library:

!*

This was used to make a special folder of .rsts that would be included in the repo. I was naively ignoring on match any of the relevant .gitignores, but it seems like I would have to actually consider the exclusions / un-exclusions on the rule level and combine them there to handle something like this.