.rosinstall文件改成Gitee源

 # Install wstool and rosdep.

    
 $ sudo apt-get update
    
 $ sudo apt-get install -y python-wstool python-rosdep ninja-build
    
  
    
 # Create a new workspace in 'cartographer_ws'.
    
  
    
 $ mkdir cartographer_ws
    
 $ cd cartographer_ws
    
 $ wstool init src
    
  
    
 # Merge the cartographer_turtlebot.rosinstall file and fetch code for dependencies.
    
  
    
 $ wstool merge -t src https://raw.githubusercontent.com/googlecartographer/cartographer_turtlebot/master/cartographe