Some extension classes are not within the right namespace

[edwinvandriel]

I've noticed that some extension classes are not within the Microsoft.Toolkit.Uwp.UI.Extensions namespace.

Extension classes that are not within this namespace but in Microsoft.Toolkit.Uwp.UI are:

• HyperlinkExtensions
• ListViewBaseExtensions
• VisualTreeExtensions
• WebViewExtensions

The extension classes that are in Microsoft.Toolkit.Uwp.UI.Extensions namespace:

• ApplicationView 👍
• StatusBar 👍
• TitleBar 👍

[Odonno]

I am not sure if it is on purpose but I can see on the git history that we removed the Extensions namespace.

I think @hermitdave has an idea.

[hermitdave]

I myself stumbled upon that over the long weekend. I think we should fix that.

[nmetulev]

Agree, I'll add this as part of the breaking changes work for 2.0

[nmetulev]

Closing per #1297