Replace Any::Moose with Moo

This is a work-in-progress branch, it's not complete, but the test suite passes.

Any::Moose is deprecated. It's no longer recommended. The upgrade path is Moo, it has the same low-overhead of Mouse (actually a bit better) and a better upgrade path to Moose.

I've replaced Any::Moose with the equivalent Moo calls in this branch. The ::Types are gone, and I've moved the coercions inline.

What's missing: all isa checks are disabled for now, I'm not sure what to do here. I could enable them again, with custom checks, but I'm not sure if this is something we should invest on.

Comments? Suggestions?