Silence PyGi warnings by requiring versions before importing

Fixes #10

Author: JIghtuse

neovim_gui/gtk_ui.py

@@ -4,6 +4,10 @@
 
 import cairo
 
+import gi
+gi.require_version('Gtk', '3.0')
+gi.require_version('Gdk', '3.0')
+gi.require_version('PangoCairo', '1.0')
 from gi.repository import GLib, GObject, Gdk, Gtk, Pango, PangoCairo
 
 from .screen import Screen