useThrottledCallback etc should provide a cancel method

[dominictobias]

Like with lodash we should be able to cancel the scheduled event. i.e.:

const throttledSetValue = useThrottledCallback((value) => setValue(value), 1000)

throttledSetValue('somevalue')
throttledSetValue.cancel() // doesn't get set

• We don't want to run after unmount
• We need to cancel the action for some other reason