Run `semantic3` on imported modules, and emit new symbols with `available_externally` linkage. This allows the inliner to inline functions from other modules while telling the code generator to ignore those functions (treat them as declarations) Still generates a few extra `TypeInfo`s and strings... Disabled when generating debug info because I don't really understand it, and it doesn't like this.

#ifndef LDC_GEN_TYPEINF_H
#define LDC_GEN_TYPEINF_H

void DtoResolveTypeInfo(TypeInfoDeclaration* tid);
void DtoDeclareTypeInfo(TypeInfoDeclaration* tid);
void DtoConstInitTypeInfo(TypeInfoDeclaration* tid);

#endif