This PR modifies `specializeResetT` so that it generates the proper
reset code for range types. I've tested it in the examples for issues
issues I had been experiencing.
(cherry picked from commit 473f259268)
* refactorings in preparation for ropes elimination of the C code generator; mostly the usual ': Rope' -> 'result: var Rope' rewrite
* rewrote ccgcalls.nim
* refactored ccgexprs.nim
* ccgliterals: refactoring
* refactoring: code dealing with name mangling
* refactoring: getRecordFieldsAux
* ropes are strings (insert obscene joke here)
* optimize JS code gen
* optimizations and code improvements
* more optimizations
* final cleanups
