Clone the repository with:
$ git clone --recurse-submodules https://github.com/hdus/SRTM-Downloader
Update submodule with:
$ git submodule update --remote about
Clone the repository with:
$ git clone --recurse-submodules https://github.com/hdus/SRTM-Downloader
Update submodule with:
$ git submodule update --remote about