Porting TokenizingTextBox

[niels9001]

This PR ports the TokenizingTextBox to the new repo, addressing: #53

Changes:

• Ported over code, sample and tests.
• Visual update to the TokenizingTextBox to make it inline with WinUI styling:

Before:

After:

• Working on WASDK and UWP - couldn't figure out why it's not showing the tokens on WASM. Might be the ItemsPresenter issue we were having with SettingsExpander as well?

[niels9001]

@Arlodotexe When copying the WrapPanel code manually into the project, everything works. When referencing the .Primitives.proj I'm getting this error:

[niels9001]

@Arlodotexe did you see the crash as mentioned above?

[Arlodotexe]

@Arlodotexe did you see the crash as mentioned above?

It looks like you are referencing the primitives .csproj directly via the MSBuild property ToolkitPrimitiveSourceProject, but I'm not seeing the crash you mentioned on any platform.

Uno does appear to have an issue though. We should file a ticket to investigate this issue so it can be fixed from Uno's end.

[michael-hawker]

Didn't try testing locally yet, but just going through a few things to get up to speed. Did a comparison with Uno fork and didn't notice any big differences. I know originally, I had tested this control on Android for the Graph components, but don't think I had tried WASM at the time.