First attempt at forcing routes to return an explicit status. #20
Merge branch 'master' into topic/responsetype

Conflicts:
	core/src/test/scala/org/http4s/rho/ApiTest.scala
	core/src/test/scala/org/http4s/rho/ParamDefaultValueSpec.scala
More refinement.
Merge branch 'master' into topic/responsetype

Conflicts:
	core/src/test/scala/org/http4s/rho/ApiTest.scala
Bring api in line with the core-dsl concerning Response generation
Add some unit tests for Result and ResponseGenerator
Add some comments on tricky sections as suggested by @before