Add OpenWebRX

I received a request via email from OK1UNL to add OpenWebRX )from https://github.com/jketterl/openwebrx( which replaces the now archived HA7ILM project.

Investigated this using the Docker installation. Seems to proceed ok, but took a very long time to install. A bit concerned with the number of packages getting installed and uninstalled.

Recommend investigating the manual installation as it would provide more control over what gets changed in the system.

A lot of the packages that are install during a "regular" install are indirect dependencies. For example: wsjtx requires a whole bunch of qt5 and X packages for its graphical user interface. An installation of libsoapysdr automatically installs a the whole set of soapysdr0.6-module-* packages for hardware support.

Many dependencies are optional, so you can get a stripped down install by telling apt to leave out the recommended packages: apt-get --no-install-recommends install openwebrx. This will of course limit the available features and hardware support.