Save online maps and load them offline

1.Building:

1.1 DONOT forget to download the Vocabulary form the origin repo and place it into dir ./Vocabulary

1.2 Create a folder based on the contents of CMakeLists.txt

1.3 build

     chmod +x build.sh
     ./build.sh

only build the ORB_SLAM2 mode with pcl

    mkdir build
    cd build
    cmake ..
    make -j

2.Run:

• You can refer to the commands in the command.txt file

What are modified:

• adding a pointcloud viewer with loopclosing ( realized by adding a viewer thread )
• save map
• load map