#73 Add new script property "SetNames"

[Abderrahman Taha]

This property can be used to give choosen names to each slider set, instead of the generic names "Set_N" used in the combo box"Predefined Sets" in the "Sliders" tabulation.
example:
...
"Sliders": {
"SetNames": ["TwistedTori","InkaSun"],
....