This is just a specialized instance of Arrow in which jsPlumb hardcodes
foldback to 1, meaning the tail of the Arrow is a flat edge
Width of the tail of the arrow
Distance from the tail of the arrow to the head
Where, either as a proportional value from 0 to 1 inclusive, or as an absolute value (negative values mean distance from target; positive values greater than 1 mean distance from source) the PlainArrow should appear on the Connector
Which way to point. Allowed values are 1 (the default, meaning forwards) and -1, meaning backwards
A style object in the form used for paintStyle values for Endpoints and Connectors.