Added ability to cancel movement and drop on same position

[SiebeVE]

Ping @colinrcummings, what do you think about this PR?

[SiebeVE]

@colinrcummings Did you find the time to check this PR?

[colinrobertbrooks]

@SiebeVE, what's your use case for this behavior?

[SiebeVE]

With this extension I can properly test 2 use cases:

• When the movement is canceled (here simulated by pressing the esc key)
• When the movement isn't cancelled, but dropped in the same position

With the current library you aren't able to do it because it expects a movement and you can't cancel a movement.