typo
tersifying the Pyret stack
adding all2
lots of missing visit() calls on annotations, and fixing the handling
of assignments to unbound variables -- they're not globals; they're
simply missing, so leave them for the next pass to catch, rather than
killing the compiler
more tersifying of stack traces
Nearly-complete extraction of skeletons from Pyret modules.  now handles parametric types, most common forms of cross-module linking, and richly structures the contracts to include the cross-ref information.  Still todo: extract the global namespaces, and render everything...