Allows QuickCheck2 properties to be used with the test-framework package.

For an example of how to use test-framework, please see http://github.com/batterseapower/test-framework/raw/master/example/Test/Framework/Example.lhs

Due to technical limitations of the QuickCheck2 package, it's not possible to correlate arguments that caused the failure with the particular Test that caused them. This means that the arguments to your properties that lead to failure will be printed at non-deterministic positions in the stdout stream. Sorry.