Handle computed literals in cdef
Created originally on Bitbucket by ernwa (Andrea Waite)
- parse int, char, float, string literals and #defines
- detects and captures the value of constant expressions in #defines
- can ingest unmodified .h files from real c projects now
- Using “proper” AST parsing cribbed from pull request #30 (closed). Support unary, binary, ternary ops.
- passes all but a few tests related to re_python; generates different code than expected or generates "SystemError: Objects/longobject.c:1024: bad argument to internal function", probably related to integer handling (added support in int parser for LL & ULL as python long type)