Added non-specialized signature for slider(methodName, values)

Compiling the current version with the new TS 0.9.1.1, the compiler stopped with "error TS2154: Specialized overload signature is not subtype of any non-specialized signature."
As a matter of fact the non-specialized signature for the slider(methodName, values) overload was missing.
I added it and everything compiles smoothly. 
Try it yourself
Have a nice day!