bunch more __all__ lists
also modified check_all function to suppress all warnings since they aren't
relevant to what this test is doing (allows quiet checking of regsub, for
instance)
diff --git a/Lib/sched.py b/Lib/sched.py
index fc5bd56..ba5f33a 100644
--- a/Lib/sched.py
+++ b/Lib/sched.py
@@ -30,6 +30,8 @@
 
 import bisect
 
+__all__ = ["scheduler"]
+
 class scheduler:
     def __init__(self, timefunc, delayfunc):
         """Initialize a new instance, passing the time and delay