Improve warnings for KBM (dev/build-features) (#2386)

* Handled invalid input for single key remaps

* Added some functions

* Added better error message functions and finished warnings for edit keyboard

* Updated dropdown order of keys

* Added new warning template for shortcuts

* Added show warning on Apply code

* Removed old flyout code

* Fixed issue where tooltips were replaced on Apply

* Simplified == operator

src/modules/keyboardmanager/common/KeyboardManagerConstants.h

@@ -35,4 +35,7 @@ namespace KeyboardManagerConstants
 
     // Name of the dummy update file.
     inline const std::wstring DummyUpdateFileName = L"settings-updated.json";
+
+    // Initial value for tooltip
+    inline const winrt::hstring ToolTipInitialContent = L"Initialised";
 }