Add a new contextmenu menu item
addItemContextmenu(map, option)A leaflet map object
a map widget object created from leaflet
new menu item to add
Other Contextmenu Functions:
addContextmenu(),
context_mapmenuItems(),
context_markermenuItems(),
context_menuItem(),
disableContextmenu(),
enableContextmenu(),
hideContextmenu(),
insertItemContextmenu(),
mapmenuItems(),
markermenuItems(),
menuItem(),
removeItemContextmenu(),
removeallItemsContextmenu(),
setDisabledContextmenu(),
showContextmenu()