Improve reporting keyboard layout changes (#8401)
* Improve reporting of keyboard layout changes.
In particular, fixes the problem of reporting the same keyboard layout over and over, alternating between a message with and without language name.
* Don't report if there is no change, typically on TSF profile (de)activation.
* Query the keyboard layout when NVDA starts instead of starting without a value. The previous implementation caused the first layout change to always be announced, even if the old and new layouts were identical.
* Don't allow the input method name (two placeholders separated by a hyphen) to be translatable.
* Fix a log message.
* Improve comments.
* Add copyright header.
* Remove XP code for TSF from NVDAHelper.dll.
* Update copyright header.
* Use the LOWORD macro to get a lo-word.
* Review actions.
* Review actions.
* Update what's new
