Make error rpython compatible
Make ast nodes inherit from a common node for rpython compatability
Use an explicit class for char ranges instead of a named tuble to make rpython happy
Fixup lexer to work for rpython
Make parser rpython compatible
Put some default functions into the visitor, for stuff that you do not alwayes want to visit
Make the json priter type checkable by rpython
Make first parse work with rpython, there currently is a bug in substrexpr
Fix up RASMUS to also be an rpython target
Add some rpython targets to the makefile