Hervé Girod - 2018-06-10

Change the handleLeftClick method of the GutterHandler interface by handleClick to allow to handle any click
Add a handleMoved method in the GutterHandler interface to allow to show tooltips, for example upon hovering on the Gutter
Add an AbstractGutterHandler class which simplifies showing custom images on line numbers, and handling tooltips
Use docJGenerator 1.2.2 for the wiki