feat(windows): Improve user visibility of Base Keyboard setting

In the non-Qwerty world, it is necessary to configure the base keyboard when Keyman is installed. The implication if one fails to do this is clear to me, but not to an un-assisted user. A new user is likely to be confused later if they install a mnemonic keyboard or happen to press a key combination not defined in the keyboard and they receive the US QWERTY fallback glyph. Some developers assume a physical keyboard and only define the characters that are different from the base keyboard. Others, like me, overdefine to avoid unexpected fallback.

**Is your feature request related to a problem? Please describe.**
For a Non-Qwerty machine and a mnemonic keyboard, it is critical that the Base Keyboard be configured properly, as the default seems to always be English US. If a non-mnemonic keyboard is chosen, and a key combination is undefined (i.e. SHIFT+RALT+2), I believe Keyman will draw the resulting character from the "Base Keyboard", which may be unexpected.
Base Keyboard configuration is not obvious and is never signaled to the user, the configuration is buried, and the process requires Admin rights. This might be more helpful if the user was prompted to confirm the Physical keyboard during Keyman or Keyboard install, when admin rights have already been given.

**Describe the solution you'd like**
If the Default Windows Keyboard on the machine is something non-US-QWERTY as Keyman is installed. I suggest a pop-up:
"It looks like your computer may be using a physical [French (France) AZERTY] keyboard, but Keyman is configured to expect [US English QWERTY]. Some Keyman keyboards may need to know your computer's physical keyboard to work properly. Would you like to configure Keyman to use [French (France) AZERTY] as the physical keyboard?"
[Yes] [Choose a different Base Keyboard] [Help me Identify my Keyboard] [No/Cancel]

The Help button could take the user to a Ubuntu-Install-type button pushing exercise until the exact physical keyboard is determined and shown on the screen.
https://askubuntu.com/questions/384758/name-of-detect-keyboard-layout-tool
Or minimally, this page:
https://keyshorts.com/blogs/blog/44712961-how-to-identify-laptop-keyboard-localization

**Describe alternatives you've considered**
Alternately, the user could be asked to confirm the physical keyboard the first time a Mnemonic keyboard is installed, but then they may need to elevate to Admin.

**Notes**
I have had issues in the past with Keyman ignoring the Base Keyboard and insisting on QWERTY, but I believe this is fixed in recent versions.

**Keyman for Windows/macOS/Linux:**
Since Mnemonic only works on Windows, this is priority, but I expect this may be needed in Mac/Linux for undefined combinations.