SegmentedControl element

[shuyangli]

Feature request

Would be great to have a prepackaged SegmentedControl component, instead of requiring consumers to roll their own. Something like this:

blueprint/packages/docs-app/src/examples/core-examples/common/alignmentSelect.tsx

Lines 17 to 36 in 1252adc

	export class AlignmentSelect extends React.PureComponent<IAlignSelectProps> {
	public render() {
	const { align, allowCenter = true, label = "Align text" } = this.props;
	return (
	<div>
	{label}
	<ButtonGroup fill={true} style={{ marginTop: 5 }}>
	<Button active={align === Alignment.LEFT} text="Left" onClick={this.handleAlignLeft} />
	{allowCenter && (
	<Button
	active={align == null || align === Alignment.CENTER}
	text="Center"
	onClick={this.handleAlignCenter}
	/>
	)}
	<Button active={align === Alignment.RIGHT} text="Right" onClick={this.handleAlignRight} />
	</ButtonGroup>
	</div>
	);
	}