* A graph now properly saves and restores when it has an attribute on its second Y-axis.
* Color of 2nd y-axis label is now properly set to match the color of the dots
* The 2nd y-axis only highlights during a drag if it is appropriate to drop an attribute there
* Moved tooltip axis label string into strings.js
The attribute menu on the y2axis now works and can be used to remove or replace the current attribute.
Minor adjustments to opacity of colored dots