This directory does not host a real plugin, only source files other
lib_gtkN_common and hid_gtkN_* plugins can use. The idea is to have
all-gtk-version-common code here while being able to put
per-version-common code in the respective plugin.

Naming convention in this directory:

util_*: generic, non-UI related utilities
ui_*: ui logic related, but gtk-free utilities
wt_*: custom widgets, cell renderers for gtk - must work in both gtk2 and gtk3
dlg_*: dialog boxes, preferably one per file
bu_*: builders, building a part of a bigger gui portion
in_*: input handling (gtk-specific)
glue_*: glue code that should be used by the HID implementations to interface the HID API or by the gtk code to interface the HID implementation


Naming convention in lib_gtkN_common/:

compat.h: compatibility layer for various GTK versions


Any of these may depend on glib.
