* generate different versions of binary operators
for each size of int and float, so that proper
truncating happens after each operation to
simulate the various sized ops.
* add slice expressions
* publish World.CompileStmtList, CompileDeclList, CompileExpr
* handle type-less expressions in CompileExpr
R=austin
DELTA=1459 (1327 added, 11 deleted, 121 changed)
OCL=34382
CL=35581