GAAS prebuilt dependencies

Here we provide a prebuilt deb packages for the dependencies of SLAM, including those following Projects:

# PCL
https://github.com/PointCloudLibrary/pcl
# DBoW3
https://github.com/rmsalinas/DBow3
# g2o
https://github.com/RainerKuemmerle/g2o
# opencv version 3.4.5 including contribs
https://github.com/opencv/opencv
# pangolin
https://github.com/stevenlovegrove/Pangolin

The debs can be used on Ubuntu 16.04 and Ubuntu 18.04 on x86-64, just extract and run:

sudo dpkg -i *.deb