Allow user to move waypoint when outside of other axis bound

[jasondaming]

Reimplementation of: Closes #108

Closes #95

Only the respective axis is considered when checking the bounds. This doesn't help with being far out of the pane but that is a bigger issue and something I don't think we need to support as the cursor turns to indicate a problem

[sciencewhiz]

If both of those checks fail, is should the path be recalculated and updated?