Fifth cut of plugin rework; strip redundant 'wp_biographia_' prefix from configuration options.
Update plugin's pointers to use latest version of WP_PluginBase
Update plugin uninstaller to remove user meta with 'wpb_' prefix.
Sixth cut of plugin rework: separate plugin upgrade from wp-biographia-admin.php to wp-biographia-upgrade.php
Must remember to strip out error_log before committing!
Seventh cut of plugin rework; add Co Authors Plus support.