Add a -v (and -vv) flag and decrease default message verbosity.

helpers.py

@@ -1,8 +1,17 @@
 import sys, os
 
 logprefix = ''
+verbose = 0
 
 def log(s):
     sys.stdout.flush()
     sys.stderr.write(logprefix + s)
     sys.stderr.flush()
+
+def debug1(s):
+    if verbose >= 1:
+        log(s)
+
+def debug2(s):
+    if verbose >= 2:
+        log(s)