Support moving the segment. #55

const handleSegmentPress = React.useCallback(
		(e) => {
			const clientX = e.type === 'touchmove' ? e.changedTouches[0].clientX : e.clientX;

			const onDrag = e => handleSegmentDrag(e, clientX);
			const handleRelease = e => {
				const {
					tempValues,
					values,
					onChange = () => {},
				} = getLatest();

				document.removeEventListener('mousemove', onDrag);
				document.removeEventListener('touchmove', onDrag);
				document.removeEventListener('mouseup', handleRelease);
				document.removeEventListener('touchend', handleRelease);
				const sortedValues = sortNumList(tempValues || values);
				onChange(sortedValues);
				onDrag(sortedValues);
				setTempValues();
			};

			document.addEventListener('mousemove', onDrag);
			document.addEventListener('touchmove', onDrag);
			document.addEventListener('mouseup', handleRelease);
			document.addEventListener('touchend', handleRelease);
		},
		[getLatest, handleSegmentDrag]
	);

const handleSegmentDrag = React.useCallback(
		(e, initialX) => {
			const clientX = e.type === 'touchmove' ? e.changedTouches[0].clientX : e.clientX;
			const initial = getValueForClientX(initialX);
			const newValue = getValueForClientX(clientX);
			const diff = newValue - initial;
			if (diff) {
				let actualDiff = 0;
				if (diff > 0) {
					const last = values[values.length - 1];
					const newRoundedLastValue = roundToStep(last + diff);

					actualDiff = newRoundedLastValue - last;
					
				} else {
					const first = values[0];
					const newRoundedFirstValue = roundToStep(first + diff);
					actualDiff = newRoundedFirstValue - first;
				}

				if (actualDiff) {
					setTempValues(values.map(v => v += actualDiff));
				}
			}
			
		},
		[getValueForClientX, roundToStep, values]
	);