Test work on all browsers even when paths go from right to left
Cleaned up path parsing a bit
Now draws lines in response to mouse movement
Basic line drawing in response to drag is in place.
Code correctly saves off start position when mouse button goes down
Fleshed out tests with additional 'normal' cases
Factored out relative offset calculation
Made drag state handling a bit more compact
Factored out drag event handlers
Removed extraneous drawline() test
Cleaned up test helper functions
Factored out pageOffset method
Factored out common mouse event test code
Lines are only drawn when drag starts within drawing area