* src/files.c (action_obstack): Remove, unused.

* src/files.c (action_obstack): Remove, unused.
(output_obstack): Remove it, and all its dependencies, as it is no
longer needed.
* src/reader.c (epilogue_set): Build the epilogue in the
muscle_obstack.
* src/output.h, src/output.c (muscle_obstack): Move to...
* src/muscle_tab.h, src/muscle_tab.h: here.
(muscle_init): Initialize muscle_obstack.
(muscle_free): New.
* src/main.c (main): Call it.