Paths can be negated to stop searching through the remaining patterns in
a the glob list. All changed files tested and at least one matching file
will result in a label being added.

Fixes actions#9

A new "rich" matcher object can be provided instead of a normal glob.

The matcher object has two fields that accept an array of globs:
* Globs in "all" must all match every changed file.
* Globs in "some" must all match at least one changed file.

Combined with negated globs, this allows for a precise control of when
labels are applied.