Surface methods should be replaced by new core methods in the reference

Processing 4 added new core functions to replace the surface methods as can be seen in the Beta 5 and Beta 7 release notes. These changes are also mentioned here https://github.com/processing/processing4/issues/53

The reference needs to be updated to reflect those updates:

• windowResize(w, h) replaces surface.setSize(w, h)
• windowResizable() replaces surface.setResizable() (reference)
• windowMove(x, y) replaces surface.setLocation(x, y) (reference)
• windowTitle() replaces surface.setTitle() (reference)
• new windowResized() event handler
• new windowMoved() event handler

In case you want to contribute to this task, here is how to edit the reference.

Note: surface methods are still backwards compatible but you are encouraged to use the new methods for future sketches

Start with docs/reference.md and the linked reference pages for setResizable, setLocation, and setTitle. Update the reference to describe the six listed window methods and event handlers, then verify that every checklist item is covered and the legacy surface methods are identified as backward compatible.