Many dependencies required on Ubuntu 18.04

[hobson]

./waf --configure will fail if build_debian.sh is not first run

[alastair]

Hi, thanks for the PR!

We have instructions to install dependencies on the essentia website: https://essentia.upf.edu/installing.html#installing-dependencies-on-linux
This script that you included appears to be a helper for a very specific task (building the music extractor), and so doesn't fit well as a general-purpose helper tool.
If you still think that there is a good reason to keep this script then please let us know your reasoning behind it.