feat(css): support for text-overflow

[NathanWalker]

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What is the current behavior?

text-overflow was not supported. This means most buttons would truncate awkwardly like this by default:

What is the new behavior?

Adds support for standard CSS text-overflow to combine with white-space to achieve different truncation on text with labels and buttons. This allows you to set text-overflow: ellipsis to allow desired truncation:

ref: NativeScript/tailwind#189
closes #5487

[edusperoni]

I believe an enum or even just a const variable would e better than a namespace

[NathanWalker]

This just maintains the current consistency in core. Changing needs a more holistic core refactor.