Add more information to drop process to be used in callback function.

[rburone]

Add the keys used in the process of drag and drop. Add the origin elment where the dragged element comes from.

[logicbomb]

No, the format is good, but could you clean this commit up some.

You can use rebase to squash commits and keep them more focused.

For example 0a0cdf4, e004b87, and bb8febf can all be combined into a single commit that reports the special keys being presseed.

Also commits 77f2f29, 249508c, eeeea51, and 9ce3944 can be squashed into a single commit that adds the fromElement to the callback.

[rburone]

Well. I think that i did the squash.