membership_visible to simplify code and fix bugs 607 and 607.

	is_supervisor_of_conf.  Callers updated.  Avoid calling
	access_perm if possible.  Grant full access if ENA(admin,2) or
	ENA(wheel,8), as do_get_members did.
(do_get_members): Use membership_visible to simplify code, and fix bug 705.

(check_unread): New static function.
(membership_visible): New static function, that fully implements
	the membership visibility rules that were documented
	2002-08-07.
(get_unread_confs): Use membership_visible to simplify the code
	and use the correct membership visibility rules.  Various code
	cleanup. (Bug 597).

persons.

censor the secret conference, since the viewer is supervisor of the
member.

SMALLOC_MAGIC_FREE. (Bug 562).

(SMALLOC_MAGIC_FREE): Ditto.  (Bug 562).

	USE_MALLOC_GUARDS is true.
(SMALLOC_MAGIC_FREE): Ditto.  (Bug 562).

	aux-item-def-parse.h.

(kom_delete_text): New function. Use to delete a text from the test suite.

Added missing test cases for bug 84 and one xfail for bug 690.

dbck.  Make it possible to run lyskomd without malloc guard areas.
Fixed a read past the end of a buffer.  Fix the l2g test cases.

--with-valgrind, but should not be used in a production setting.

(OVERHEAD): New macro, that computes a size including the guard
	area overhead.  Two versions, depending on if
	USE_MALLOC_GUARDS is defined or not.
(smalloc): Reindent.  Test USE_MALLOC_GUARDS.
(sfree): Test USE_MALLOC_GUARDS.
(srealloc): Test USE_MALLOC_GUARDS.

(dbck_run): Ditto.
(spawn_lyskomd): New argument: log file name.  All callers
	updated.  Use the lyskomd.supp valgrind suppressions file.
	Pass --show-reachable=yes and a log file name to valgrind.
(check_valgrind): New arguments: logfile, need_leaks and need_errs.
	All callers updated.

(EXTRA_DIST): Added lyskomd.supp.

	s_strtol, s_strtol would attempt to read the sign ('+' or '-')
	past the end of the string.

works properly.