Abstract

Added a GtkEntry on header to customize sample text. The box is hidden in overview mode, while in preview mode it gets visible and grabs the keyboard to enter text. The text is passed to sushi_font_widget via a GObject property I added (a property change fires a redraw).
WRT issue #33, I included a .css file in the resource to generate 18px of padding. The provider is loaded and added to the context of the drawing area in sushi_font_widget_draw (only once).
I tried to substitute pango_find_base_dir (which is deprecated) with fribidi_log2vis (I added fribidi in meson.build as a dependency). It's a bit of a dirty hack.

A word of warning

I've done no gtk programming prior to this afternoon, so please review carefully and be patient.