Allow by-string matching in throwError

[pkozlowski-opensource]

As of today the throwError matcher accepts arguments of type being either:

• a regexp
• a function

Personally I find myself quite often matching the error message literally and in this case escaping regexp special chars is a bit of chore. Could we also accept strings as arguments and use the == / === operator to match this string against the error message?

This would definitivelly make my life a bit easier, happy to send a pull request if this meakes sense.

[janmarek]

Yes please.

[janmarek]

I have forked this library https://www.npmjs.org/package/expect2