[doc] update airsim doc.

simulation/Airsim/README.md

@@ -1,8 +1,10 @@
 Steps to start airsim:
-0. setup env.
+
+Setup env:
+
     mkdir -p ~/Downloads/Airsim/ && https://github.com/microsoft/AirSim.git && cd ~/Downloads/Airsim/AirSim && git checkout v1.5.0-linux
 
-    # install airsim with the scripts setup.sh and build.sh manually.
+    #install airsim with the scripts setup.sh and build.sh manually.
 
     sudo ln -s  /usr/lib/x86_64-linux-gnu/libstdc++.so.6  /usr/lib/x86_64-linux-gnu/libstdc++.so  # for clang+llvm we need cpplib files end with .so.
 
@@ -12,29 +14,30 @@ Steps to start airsim:
 
     cd ~/Downloads/Airsim/AirSim && ./build.sh
 
-1. prepare for simulation:
+
+step<1> prepare for simulation:
 
     cp simulation/Airsim/mavros_launch/* /opt/ros/melodic/share/mavros/launch/px4_airsim.launch
 
     cp ~/GAAS/simulation/Airsim/vehicles/{YOUR_VEHICLE_CONFIG_FILE} ~/Documents/AirSim/settings.json
 
-2. start airsim simulator:
+step<2> start airsim simulator:
 
     cd ~/Downloads/Airsim/${MAP_NAME}/LinuxNoEditor && ./${MAP_NAME}.sh
 
-3. start px4 simulation:
+step<3> start px4 simulation:
 
     cd ~/Downloads/Airsim/AirSim/PX4/PX4-Autopilot && make px4_sitl_default none_iris
 
-4. start mavros for airsim.
+step<4> start mavros for airsim.
 
     roslaunch mavros px4_airsim.launch
 
-5. start airsim sensor msgs publisher.
+step<5> start airsim sensor msgs publisher.
 
     cd ~/Downloads/Airsim/AirSim/ros && source devel/setup.bash && roslaunch airsim_sensors airsim_sensors.launch
 
-6. (optional) start QGroundControl.
+step<6> (optional) start QGroundControl.