feat(windows): differentiated keyboard icon when using same keyboard in multiple languages in language indicator

Per [bart_eenkhoorn1 on Keyman Community Site](https://community.software.sil.org/t/how-to-improve-west-africa-keyboards-french-accents-and-spell-check-in-ms-word/9341/7):

> Thank you again for your contributions. As it turns out, the keyboard is producing composed french very well indeed ! However, the keyboard was not linked to the french language (as a tag) in keyman :-( .
> After correcting that we now have one kmx file linked to three languages in the keyman configuration settings. This works very well, with an added difficulty.
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> For each of these 3 languages the same icon is displayed by keyman. So the unaware user may think he or she is ok, but in MSWord one may find this:
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> So indeed it is very helpfull that one can add the same keyboard to multiple languages in Keyman Configuration, but the question is how to make that visible for the user? When MSWord is launched it will switch to the current language that is active in Keyman. As far as I am aware, the user will then have to manually change the language of the new document via the language settings menu:
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> Is there a solution to display a different icon for each language selected within one kmx file? If not, what help could we offer the user to make him or her aware which keyboard is selected?
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