More fixes that make autotools working for the empty repo

- Add a dummy lemon/list_graph.h file and put it in the Makefile.am
- Remove the unnecesary icons from doc/icons/geom folder.
- Update .hgignore

 EXTRA_DIST += \

 	test/Makefile

 noinst_HEADERS +=

 check_PROGRAMS +=

 TESTS += $(check_PROGRAMS)

 XFAIL_TESTS += test/test_tools_fail$(EXEEXT)