Set inertia status to inactive after final move
Add snap and restrict status to debug object
Improve snap and restrict with zeroResumeDelta
Move inertia calculations into separate function
Implement smooth snap/restrict

It happens if inertia is enabled and endOnly is enabled on
snap/restrict and the pointer is released without activating regular
inertia and a snap/restrict occurs.
Fix a bug when both snap and restrict happen
Improve code for inertia and smoothEnd
Inertia and smoothEnd snapping on the right action
Tidy code a little in pointerUp
Add "smoothEndDuration" option to inertia
Add 'dropmove' event type

interact('.dropzone')
    // enable draggables to be dropped into this
    .dropzone(true)
    // listen for drop related events
    .on('dropmove', function (event) {
        // Do something here
    });

the event object looks like

{
  target: dropzoneElement,
  dragmove: dragmoveEvent,
  type: 'dropmove'
  ...
}
Fix setOnEvent for 'dropmove'
Add snap elementOrign and restrict elementRect

interact('*').snap({
  elementOrigin: { x: 0, y: 0 }
});

elementOrigin.x/y are scalars specifying the position on the element to
which snapping should be relative.

{x:   0, y:   0} is the top left
{x: 0.5, y: 0.5} is the center
{x:   1, y:   1} is the bottom right

interact('*').restrict({
  elementRect: { top: 0, left: 0, bottom: 1, right: 1 }
});

For the left and right properties, 0 means the very left of the element
and 1 means the very right. For top and bottom, 0 means the top of the
element and 1 means the bottom.

{ top: 0.25, left: 0.25, bottom: 0.75, right: 0.75 } would result in a
quarter of the element being allowed to hang over the restriction edges.
Fix bugs in restrict methods
Fix bugs in snap and restrict

 - make snap.elementOrigin `null` by default
 - fix a bug when restricting without elementRect
Fix inacurate restriction when starting near edge

... while elementRect is set
Calculate snap, restrict offsets once at start
Merge branch 'master' into snap-restrict-element-rect
Try to fix restriction and snap with resize
Clear inertiaStatus.resumeD{x,y} at the right time