Fix g_thread_init() and g_type_init() deprecations.
Fix g_thread_create() deprecation..
Replace gdk_cursor_unref() with g_object_unref()
Conditionalize use of gtk_widget_size_request
Conditionalize use of gdk_keyboard_grab/ungrab().
Conditionalize use of gdk_pointer_grab/ungrab().
Conditionalize use of gdk_pointer_is_grabbed()
Conditionalize use of gdk_display_get_pointer()
Conditionalize use of gdk_app_launch_context_new()
Conditionalize use of gdk_display_get_pointer() 2
Fix run-time errors:
Conditionalize use of g_mutex_* and g_cond_*