* coop.c: #include <errno.h>

* coop.c: #include <errno.h>
(coop_timeout_qinsert): Moved here from iselect.c
(coop_new_mutex_init, coop_new_condition_variable_init): New
functions.  The strange names are temporary.  Use scm_mutex_init
and scm_cond_init instead.
(coop_mutex_trylock): New function.  Uses errno.h:EBUSY.  errno.h
is ANSI C, but should we check for individual error codes in
configure.in?
(coop_condition_variable_timed_wait_mutex): New function.
(coop_key_create, coop_setspecific, coop_getspecific,
coop_key_delete,