Fix performance hotspot in ==.
Fix performance hotspot in ==.

The new == implementation was recursively calling itself to compare 
classes. This was a huge time sink. This change gets it back down to
something closer to reasonable.
munificent/magpie,munificent/magpie,munificent/magpie-csharp,munificent/magpie-optionally-typed,munificent/magpie,munificent/magpie-optionally-typed,munificent/magpie,munificent/magpie,munificent/magpie-optionally-typed,munificent/magpie-optionally-typed,munificent/magpie-optionally-typed