Fixing request animation frame callback issue. (#31)

The issue could result in multiple animation frame requests in succession
cancelling one another out. Can result in choppy interactions or what looks
like an update issue.

add builds

Only prevent default of a mouse down event when something is selected.

Merge pull request #5 from mapd/ricky/cursor-should-revert-when-shape…

…s-are-deleted

Added default cursor logic to delete methods

Set entrypoint to the built prod module