Rename Handler to Action.
WIP.
POC of special Groovy DSL.
expanded groovy sample test a little.
Update spec.
Apply groovy plugin to core project so that tests execute during build
Add clover plugin to the build
Fix another spec.
Fix another spec.

Had to drop test for error handling on threads as there's no strategy for that yet.
Shuffle some specs around.
rename.
Merge branch 'clover' into ld-rewrite
Do not apply clover to ratpack-groovy as there seem to be some compilation problems when doing that
Fix up injected handlers.
Moved some classes.
Added some notes on the injecting handler.
move.
More spec fixing.
Move the Groovy test support test to the test support package.
Fix template handling (and error handling)