Update documentation on how to use Powershell module on Linux

[devopsvnext]

The current Powershell documentation appears to be very Windows focused.

From what I understand, the PowerCommander module is supported on Linux to some extend.

It would be great to have the documentation updated, so it becomes easier and faster to get started with the module on Linux.

Hopefully there is a business case for this. Many Windows shops are migrating to Linux and will appreciate being able to use Powershell on Linux. That is certainly the case in our case.

Thanks!

[devopsvnext]

For instance here:

https://github.com/Keeper-Security/keeper-sdk-dotnet/tree/master/PowerCommander
https://docs.keeper.io/en/secrets-manager/commander-cli/commander-installation-setup/installation-on-powershell