Need to remove PYTHONHOME environment variable in order to run under Windows

[kheckwrecker]

When running the latest version of master in Windows (as of today), it fails with a Python error. Manually unsetting PYTHONHOME and re-running the game works. Based on limited googling, I found a comment that PYTHONHOME should never be set as it generally causes problems.

[kheckwrecker]

This issue is also a problem when compiling under Windows. In order to successfully run build.ps1, this environment variable needs to be unset first.

[kheckwrecker]

For additional information, this is what the PYTHONHOME environment is set to on my computer.

C:\Projects\v\packages\python3_x64-windows\tools\python3

To remove it, in a command prompt, I just need to type set PYTHONHOME=