1st Loop namespace and functions created

If no design mission can be found yet, a 1st loop version of mission analysis is run. Only the following values are written in that mode:

• range (which is equal to the required range)
• loaded_mission_energy/mission_energy
• in_flight_energy/trip_energy
• taxi_energy/taxi_out_energy
• taxi_energy/taxi_in_energy

Please check if we can get into the next loops with this solution

mission_analysis/mission_analysis_conf.xml

@@ -228,9 +228,9 @@
 				<center_of_gravity_method description="Selector to shift the center of gravity: mode_0 (Off) / mode_1 (half-sophisticated with howe for lifting surface tank) / mode_2 (sophisticated method for center of gravity (only payload and fuel) calculation)">
 					<value>mode_0</value>
 				</center_of_gravity_method>	
-                <estimate_fuel_calculation description="(Design mission only!) If the design needs more than 1 loop to reach a sensible configuration, keep estimating the whole mission fuel (Breguet) without calculating the mission itself. Switch: true (on) / false (off)">
+                <use_fuel_estimation_method description="(Design mission only!) If the design needs more than 1 loop to reach a sensible configuration, keep estimating the whole mission fuel (Breguet) without calculating the mission itself. Switch: true (on) / false (off)">
                     <value>false</value>
-                </estimate_fuel_calculation>		
+                </use_fuel_estimation_method>		
 			</mission_methods>
 			<rate_of_climb_switch description="Switch THAT ONLY AFFECTS THE REQUIREMENTS MISSION. Calculate an optimum for the rate of climb. Switch: true (calculate optimum) / false (skip)">
 				<value>false</value>