gtk gui frontend

[Aeva]

Nothing fancy, probably using tkinter for portability reasons went with gtk.

Some remaining things to do:

• hook up the converter scripts
• progress visualizer window
• update progress window while converting levels
• "progress completed" popup
• run converters in a thread pool
• license text in about page
• order of path chooser buttons should be changed, so that tileset happens after sprites dir.
• when the sprites dir is picked, I think that means the "current_folder" for the tileset could be set, making it a little easier to find your tileset.
• clear the level list when finished
• freeze main window while converting levels
• don't render paths redundantly / consolidate redundant level paths
• generate the tileset xml file #14
• file paths in export should be relative, not absolute (to where?) #14
• program icon
• relative paths in tree view
• multi-nesting of directories in tree view
• tree view icons (folder vs level)
• the add level dialogue's working dir should either be the directory of the last level added, or the executable's working dir
• drag-and-drop

[Aeva]

For reference with the tree view stuff:

• http://python-gtk-3-tutorial.readthedocs.io/en/latest/treeview.html
• https://developer.gnome.org/gnome-devel-demos/stable/treeview_cellrenderertoggle.py.html.en
• http://arstechnica.com/information-technology/2009/08/howto-an-introduction-to-gtk-treeviews-and-autocompletion/

[Aeva]

I'm going to consider this closed now, since all of the essential features are here now, and will move the refinements into other tickets.