First pass. Status codes such as NotFound are not a clean as they once were.
Merge remote-tracking branch 'origin/develop' into topic/responsebuilder

Conflicts:
	blaze-server/src/main/scala/org/http4s/server/blaze/Http1ServerStage.scala
	blaze-server/src/test/scala/org/http4s/server/blaze/ServerTestRoutes.scala
	build.sbt
	core/src/main/scala/org/http4s/Status.scala
	dsl/src/main/scala/org/http4s/dsl/package.scala
	server/src/main/scala/org/http4s/server/websocket/package.scala
	server/src/test/scala/org/http4s/server/MockRoute.scala
	server/src/test/scala/org/http4s/server/middleware/EntityLimiterSpec.scala
	server/src/test/scala/org/http4s/server/middleware/TimeoutSpec.scala
A refinement of response generator syntax.
Refine the Status / ResponseGenerator syntax.