Whenn called with no to be completed missions hook was set 2 times

diff --git a/MissionControl.lua b/MissionControl.lua
index c03c756..8d8e7ec 100644
--- a/MissionControl.lua
+++ b/MissionControl.lua
@@ -256,6 +256,7 @@ function module:GMC_OnClick_Run(this,button)
 	do
 		local elapsed=0
 		local co=coroutine.wrap(self.GMCRunMission)
+		self:Unhook(GMC.runButton,'OnUpdate')
 		self:RawHookScript(GMC.runButton,'OnUpdate',function(this,ts)
 			elapsed=elapsed+ts
 			if (elapsed>0.25) then