Fixed a potential null reference exception inside the IntelliSense feature

If IntelliSense is used before the PowerShell Tools package has completely loaded, an object reference will be shown.

Fixed issue with license check on none-English operating systems

An invalid DateTime error would be shown when checking a license on a non-English operating system.

Fixed an issue with VS Code when entering a license

Entering a new license in VS Code would result in an error referring to NewtonSoft.Json.

Added Diagnostic Option to show the PowerShell window

In the Options->PowerShell Tools->Diagnostics window you can now enable the display of the PowerShell host to allow for debugging issues with the host starting.