Add optional DisplayTitle prop for TabContainer tabs

[Nidoxs]

While working on a plugin I needed a tab within a TabContainer to change its text dynamically based on some state. This is not easy to do at the moment with TabContainer and would involve juggling key names and making sure the currently selected tab state is updated to match the new key name whenever your tab would depend on some state to define its display text.

I've added a DisplayTitle prop to the TabContainer children tabs which will be checked for before resorting to using the child key as the display title. No changes have been made to the key being used as the identifer that is passed to OnTabSelected.

• add entry to the changelog

[sircfenner]

Suggested change

	For situations where the tab's display title may change depending on some state, you
	can use the `DisplayTitle` prop within each `TabContainer` child:
	To override the text displayed on a tab, assign a value to the optional
	`DisplayTitle` field in the tab entry; see the "Comments" example below:

[sircfenner]

Thank you!