ModRM - mod 00 r/m 101 is not a pointer; it's a displacement

This also gets rid of ContextRecord::PopReference(), renamed PopValue()
to PopInstruction()
Start fixing flawed ModR/M effective address implementation

Except for register-direct operations, the ModR/M effective address is
just an offset into a segment.  In the case of register-direct, the
address of the context record's register field can be used as this is
technically an offset into the data segment.