* Previously on VS2010, the DIA2 library wasn't properly supported on
64-bit, so it needed a separate program that always ran 32-bit and
proxied operations over a named pipe.
* Now DIA2 will load correctly in 32-bit and 64-bit, so we can do the
work in-process without needing the separate exe.
* We still need to distribute dbghelp.dll and symsrv.dll, so these now
live alongside renderdoc.dll in the build/install folder with matching
bitness.
* At the same time fixed a bug I noticed where the 0-based module index
would return 0 for the first valid module and be treated as invalid.