- fixed : various issues and enhancements relating to @showloc

    -> general block on showing the "agent" and "create_landmark" side panel
    -> World / Place Profile isn't blocked/grayed out
    -> World / About Land isn't grayed out
    -> World / Region isn't grayed out
    -> "Add Landmark" on the Places / Gear menu isn't blocked/grayed out
    -> "Add Landmark" on the Places / Add menu isn't blocked/grayed out
    -> region name is visible on the world map
    -> don't gray out access to "About Land" if the user is allowed to see it

--HG--
branch : RLVa