Add an `llvm::OStream` workalike class for use with `Logger::cout()`, with the crucial difference being special handling of `llvm::Type`s so they get printed by name rather than printing their full representation (which can be positively *huge*). This allows re-enabling some logger calls that were disabled due to extreme verbosity.

#ifndef LDC_GEN_AA_H
#define LDC_GEN_AA_H

DValue* DtoAAIndex(Loc& loc, Type* type, DValue* aa, DValue* key, bool lvalue);
DValue* DtoAAIn(Loc& loc, Type* type, DValue* aa, DValue* key);
void DtoAARemove(Loc& loc, DValue* aa, DValue* key);

#endif // LDC_GEN_AA_H