Move to Moar from Parrot; unbitrot; much improved indent handling.

First is self-explanatory, second simply due to the code being untended for a
long time and easily fixed by cargo-culting a bit of code from Rakudo.

Much improved indent handling has been achieved by following the Pynie
approach much more closely. As a consequence, we now handle ifs with elses
properly (attaching a multiply dedented else to the correct parent rather than
the first available). Also adds a simple sanity test for if handling.