Add option to disable automatic prompt hook registration

[cspotcode]

I added a flag to disable automatic registration of the prompt hook. It's only for advanced situations. You do something like this in your $PROFILE:

Import-Module ZLocation -ArgumentList @{Register = $false}

[glucas]

I'd drop the Write-Host, or change it to use Write-Information (or Write-Verbose?). Right now using this with cmder I get "False" printed in every new shell and there's no straightforward way to suppress it.

[cspotcode]

@glucas Agreed; that was debugging code that I didn't mean to commit.

[vors]

@cspotcode thank you for taking a stab at it! I think cmdler is unique enough case that we should just handle it gracefully ourselves without a separate user instruction. I don't plan to merge this PR and will close it in favor of the explicit cmder hanlding at some point. If you have windows machine with cmder around, feel free to update this PR!

[vors]

Closing in favour of eb69bb5