Dial back -O level on DPH tests to speed them up

The DPH backend library will be replaced, so there is no reason to slow down validate in order to test it.
Don't run opt versions of DPH tests at all
Test Trac #8448
Error message wibbles
Test Trac #8470
Add test for #8455.
Add new test for the second round of #7667
Update tests to reflect new check for GeneralizedNewtypeDeriving
Wibbles to output regarding role annotations.
Test Trac #8469
Test Trac #8467
Test Trac #8425
Adjust performance of T783 to #8456 fix