Added a simplified ascii_to_int() implementation.

Removed dependency on hard-coded pager id. Pager id is now passed
as an environment string `pagerid' to tasks. Alternatively, this
could take space in the utcb of each task.

conts/posix/test0/container.c

@@ -15,15 +15,12 @@ int main(int argc, char *argv[]);
 int __container_init(int argc, char **argv)
 {
 	void *envp = &argv[argc + 1];
-	char *pagerval;
 
 	if ((char *)envp == *argv)
 		envp = &argv[argc];
 
 	__libposix_init(envp);
 
-	pagerval = getenv("pagerid");
-
 	/* Generic L4 thread initialisation */
 	__l4_init();