Display Unicode character for keys in HotkeySettingsControl

[traies]

Summary of the Pull Request

The LayoutMap class from KeyboardManagerCommon was moved to common in order to reuse it in HotkeySettingsControl. In order to call the c++ code from C#, the interop project was created, which serves as a C++/CLI wrapper around the native code.

References

PR Checklist

• Applies to Fluent UX: Settings #889
• CLA signed. If not, go over here and sign the CLA

Detailed Description of the Pull Request / Additional comments

• There is also the limitation that projects compiled with the \clr flag cannot use the \MT setting.
• This means the C++/CLI wrapper has to use the \MD setting, and this also applies to the common library it wraps around.
• To prevent from changing the \MT flag in common, a common-md-flag project was set up that references the same files as common: keyboard_layout.h, keyboard_layout_impl.h and keyboard_layout.cpp

Validation Steps Performed

Manually tested Keyboard Manager works properly, and HotkeySettingsControls as well.

[arjunbalgovind]

LGTM! I think the Win32 configs are still there in the common-md project, so we should remove that before merging.