[Change] Keep count of dv patrol missions done.

[Add] Added more missions to TODO list.

TODO

@@ -10,6 +10,13 @@ Vital:
   -- Event System.
     -- Like mission system, but they occur naturally/randomly.
     -- Has similar power to mission system.
+  -- More missions.
+    -- Empire shipping campaign.
+    -- FLF Nebulae campaign.
+    -- Space Trader Missions.
+    -- Misc Empire Guard missions.
+    -- Pirate Missions.
+    -- FLF Missions.
 
 Major:
   -- Unique pilot system (besides mission uniques).

dat/missions/dvaered/dv_patrol.lua

@@ -157,6 +157,14 @@ function land()
     player.pay(reward)
     tk.msg(msg_title[1], string.format(msg_msg[1], reward))
 
+    -- Increase dv patrol mission counter.
+    n = var.peek("dv_patrol")
+    if n ~= nil then
+      var.push("dv_patrol", n+1)
+    else
+      var.push("dv_patrol", 1)
+    end
+
     -- Modify the faction standing.
     if player.getFaction("Dvaered") < 70 then
       player.modFaction("Dvaered", rnd.rnd(1, num_systems/2));