Oh, right, tests.
Headers now check each other through class identity instead of names.
Reversed the variance of header identification.
Merge branch 'topic/classtagHeaders' into develop

Conflicts:
	core/src/main/scala/org/http4s/Responder.scala
	core/src/test/scala/org/http4s/ResponderSpec.scala
Fix Header.is.
Remove collectHeader boilerplate.
Failing test: raw header mixed with parsed header.
Find headers created as raw headers with header keys.
Solution, but needs to have corner cases locked down.
Another bug caught.
Backtick headers for consistency, simplify keys, lock down Seq constructors.
Merge remote-tracking branch 'origin/topic/headers' into develop

Conflicts:
	core/src/main/scala/org/http4s/Header.scala
	core/src/test/scala/org/http4s/HeaderCollectionSpec.scala
Headers: dont make new strings to remove case when comparing them
Make less lazy.
Another experiment on headers and HeaderKeys.
Move the classtag out.
parsed of parsed headers now returns the right static type.
Fix some permission issues. Need to simplify finding headers by string.
Cleaned up the structure a bit.
Don't work harder than needed.