filips123/PWAsForFirefox: PWAsForFirefox 1.3.0

To avoid infringing Mozilla trademark policies and confusing users that this project is affiliated with Firefox and Mozilla, FirefoxPWA has been renamed to "Progressive Web Apps for Firefox" (shortly: "PWAsForFirefox" or "pwas-for-firefox"). Please use one of those names when referring to this project.

The project logo and all related icons have also been changed to use the CC0-licenced fox icon instead of the official Firefox logo.

The repository URL has been changed to https://github.com/filips123/PWAsForFirefox and the AMO URL will be changed to https://addons.mozilla.org/firefox/addon/pwas-for-firefox/ soon after this release. Existing packages and GitHub links will probably continue to work as GitHub provides automatic redirects from the old repository URL, but all links to AMO page need to be changed.

Note: Unfortunately, this is still not everything I planned for that bigger update. I will hopefully have time to release it this year...

• Support for using this project on platforms without official Firefox support.
• Automatic pre-built DEB and RPM packages for Linux on ARM.

• Rebranded the project as Progressive Web Apps for Firefox (PWAsForFirefox).
• Improved the runtime installation step is reflect added support for additional platforms.