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/libl4/src/init.c

@@ -27,6 +27,8 @@ __l4_mutex_control_t __l4_mutex_control = 0;
 
 struct kip *kip;
 
+l4id_t pagerid;
+
 /*
  * Reference to private UTCB of this thread.
  * Used only for pushing/reading ipc message registers.