MSI related changes for Convergence
Ref: https://github.com/nodejs/node/issues/2520
These commits bring essentially two fixes:
- Allow node to be installed when AppData is a network share.
- Do not suggest the previous installation path when upgrading from x32 to x64 or vv.
The custom action was modified to look for the two upgrade codes that we now use.
cc @nodejs/platform-windows