Improved glob pattern matching.

[ncruces]

As discussed in #36.

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[ncruces]

I signed it!

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CLAs look good, thanks!

[ncruces]

Negative matches are not actually supported. Go regexp supports neither negative lookahead (?!), nor the Ruby's absence operator (?~) that we'd need to implement this. This returns an ErrInvalidPerlOp.

[ncruces]

To be compatible with Firebase, patterns should start with a /, and be matched against r.URL.Path (which also starts with a /).

[surma]

10/10 for the test suite! That gives me a lot of confidence. Well done.