Format based on Keep a Changelog.
- Fix sizes and positions of the plugins listbox and the "Browse release" and "What's new?" buttons so they don't collide with other widgets depending on font used (e.g. on DSx).
- Initial release: Install or update plugins from their GitHub repositories, using either the repos taken from the plugins.tdb file (updated from GitHub on first listbox fill in a session), or the github_repo namespace variable in installed plugins. For updates, makes a backup of the previous version and allows to restore it automatically.