Wrong Logic in Drag Event

[SvenPam]

Great plugin, just a little bug we found.

In the drag: function, your update function is called all the time which triggers the cropbox event. On line 225 in cropbox.js, the logic is:
if (skipupdate)
To me, it looks like it needs to be
if (!skipupdate)
Semantically this is correct, as update will not be called, it also makes call-backs a heck of a lot smoother!

Hope that helps,

Ste