TLB crawler should collect helpfile and helpcontext IDs for TypeInfo members

[ThunderFrame]

Type libraries can have helpfile and helpcontext attributes. If we collect those details, we can facilitate access to offline help, as per #1053 .

Here's an example from the Excel OleViewer:

  helpstring("Microsoft Excel 16.0 Object Library"),
  helpfile("VBAXL10.CHM"),
  helpcontext(0x0000ffff),

[ThunderFrame]

Looks like we already get the HelpContext and HelpFile with every call to GetDocumentation but we throw them away (along with the docString).

I started on implementing this until I realized that @Hosch250 already has a PR that involves the reference crawler. And, IIRC, @Hosch250 is going to work on the references code this week, so I aborted.

Looks like QualifiedModuleName, QualifiedMemberName, ComParameter and Declarations might all need HelpFile and HelpContext fields.

I suspect that most TypeInfos will use the same HelpFile throughout the library, but there might be some rogues that refer to other HelpFiles.