Bug 759316 - "Recently used" menu not updated with gegl filters
Add GimpGeglProceure to keep track of recently used GEGL operations in the filter history. The new procedure also takes care of running the op in the GEGL tool, so filters-commands.c is almost empty now. Change gimp-filter-history.c to find procedures by name instead of comparing pointers. The only thing missing now is rerunning a GEGL op with the last settings (not just showing its UI).