New features:

 * implement redesin of the autocomplete popover, fix #146
 * divider.rs: Change the margins around the divider
 * divider.rs: Add vertical spaces around the divider

Fixs:

 * Change the git url of the html2pango crate.
 * Switch the html_markup implementation to html2pango crate.
 * Execute glib-compile-resources inside the flatpak env.