Use generic lists for events.

Use the new generic list implementation instead of those insane "next"
pointers in events. Includes some cleanups.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

src/calcurse.c

@@ -75,6 +75,9 @@ main (int argc, char **argv)
   apoint_llist_init ();
   recur_apoint_llist_init ();
 
+  /* Initialize non-thread-safe data structures. */
+  event_llist_init ();
+
   /*
    * Begin by parsing and handling command line arguments.
    * The data path is also initialized here.