add UpperCaseStr and LowerCaseStr types

 I'm debating how vane this pull request is... probably quite, but with ContributorsFromGit making things more visible, I figured I'd ask to get my old commits into git (they were added by justin, which dropped my author credit) see the RT ticket for evidence.

https://rt.cpan.org/Public/Bug/Display.html?id=71133

if this branch were merged (when master is checked out) with `git merge -s ours credit-for-my-work` it will result in no changes to the current code base, but would add the patch as written to the repository. regular merge attempts will result in conflicts and are irrelevant anyways the code is already there. unfortunately it doesn't fix git blame.