yesod-test refactor/split into yesod-hspec with hooks!

[parsonsmatt]

So #1749 had me try an d implement hooks, which didn't work, because we go from TestApp site -> YesodExampleData site in the various example-runners and immediately throw that info away. So there is not a way to get hook behavior with the current implementation of the yesod-test.

I refactored it and made yesod-hspec in this repository, which follows the hspec pattern a bit more closely and allows hooks.

Not sure if this should be a huge breaking change to yesod-test or an alternative.

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[parsonsmatt]

This is the exciting thing. Now if you want a bunch of tests that share some setup, you can get it. This makes it much easier to write small tests that make small assertions and reduce code duplication.

[parsonsmatt]

hmm now that i have figured this out, i am going to try and get it into a more minimal change so it will hopefully break fewer things