Connector Class
Parent for all Connector types. When you provide a Connector definition to an appropriate jsPlumb method,
you can do so either as a String, or as an Array of the form [String, Object]. In the former case, the String
must be one of the members from this namespace, such as "Bezier" or "StateMachine". In the latter case,
the first argument to the array is the Connector name, and the second is a JS object containing
constructor parameters for the Connector, for instance
[ "Bezier", { curviness:75 } ]
Each Connector type supports its own set of parameters, with some parameters (such as stub) being shared by most.
