Undo: implement undo of depth and duration editing

This was a bit different from the other editing commands:
1) Only the current dive is edited not all selected dives.
   Therefore, create a function that turns the current dive
   into a one-element list.
2) The profile has to be replot. Here, likewise, create a
   function to do that.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

desktop-widgets/command.cpp

@@ -165,6 +165,16 @@ void editWaterTemp(const QVector<dive *> dives, int newValue, int oldValue)
 	execute(new EditWaterTemp(dives, newValue, oldValue));
 }
 
+void editDepth(const QVector<dive *> dives, int newValue, int oldValue)
+{
+	execute(new EditDepth(dives, newValue, oldValue));
+}
+
+void editDuration(const QVector<dive *> dives, int newValue, int oldValue)
+{
+	execute(new EditDuration(dives, newValue, oldValue));
+}
+
 void editDiveSite(const QVector<dive *> dives, struct dive_site *newValue, struct dive_site *oldValue)
 {
 	execute(new EditDiveSite(dives, newValue, oldValue));