Building Vely 16.6.0 from source for ubuntu_20_aarch64

Note: when you install from source, you lose the benefits of packagers, such as easy update and uninstall, and is typically not the preferred way, except for testing, software packaging etc. Follow these steps to install from source:

Get the source code from git repository, and install build dependencies:

sudo apt update
sudo apt install git
git clone https://vely.dev/dasoftver/vely.git
cd vely
git checkout 16.6.0
sudo apt update
sudo apt install devscripts equivs
mk-build-deps -i -s sudo debian/control

Make and install Vely (set DI to 1 to include debugging info - leave it as 0 for production purposes):
```
make clean
make DI=0
sudo make install
```
Install runtime tool dependencies - these are useful for running examples and tutorials, debugging and scripting:
```
sudo apt install tar curl libfcgi-bin
```

Copyright (c) 2017 DaSoftver LLC. Vely is a trademark of Dasoftver LLC. The software and information herein are provided "AS IS" and without any warranties or guarantees of any kind. Vely elephant logo (c) 2022 DaSoftver LLC. This web page is licensed under CC-BY-SA-4.0. Contact email vely@vely.dev.