MapWidgetHelper::reloadMapLocations() reloads all dive flags
of the non-hidden dives plus the one of the currently edited
dive. Use the current_dive macro to determine whether this
is the current dive site instead of the global displayed_dive_site
object.
This is part of a series of commits, which makes the map-code
independent of the global displayed_dive_site object.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>