Remove powershell script

[untitaker]

Currently install.ps1 and installer are both released in the root of the zipfile. I think that's a bit confusing. We also don't really support the ps1 script since a while.

[untitaker]

config.toml.in and rootshell are also in the main folder of the zipfile, tempted to remove those too. wdyt?

[cooperq]

were those only there to support the root shell? I think its fine to remove them. We should also update the windows documentation to remove any mentions of power shell if any exist.

[untitaker]

Removed those two files as well. the docs don't mention them

[cooperq]

LGTM!