Support for regexps in include and exclude patterns

The filter class lets people set patterns for including or excluding elements from a package, a zip, etc.

We currently support glob like patterns. It would be great to also support regular expressions.

The plan would be to let users define include or exclude patterns using regular expressions that way:

package(:zip).exclude(/\.*/)
package(:zip).include(/[C|D][0-9]*/)

Strings will still be used as glob patterns, so both mechanisms can complete each other:
package(:zip).exclude("target").include(/test-.*\.html/)