Keyword to retrieve list of context menus

[joaquimfragoso]

Similar to Issue #28 but for the context menus, like the ones we get with RightClick

[kontulai]

This is not possible to do since the context menu objects (eg. derived from JPopupMenu) are created dynamically when the right mouse button is clicked. It could be possible to implement a keyword that would list all the open context menus, but that wouldn't make sense since there can be only one context menu open at a time (at least in OSX).