Fixed multiple handler firing bug and added row highlighting for drag connections
Fixed table width bug
Dragging from left table to right results in proper highlighting
Can now draw connections from right to left
Fixed selection bug when tables contained only 1 row
Incompatible connections grey, but drawing does not reflect this
No longer snaps to incompatible rows, need to refactor drawing code
Refactored drawing code with curve class
Curve drawing finished, for now