Added scripts/crc32c.py

This seems like a useful script to have.

scripts/plotmpl.py

@@ -157,7 +157,7 @@ class AutoMultipleLocator(mpl.ticker.MultipleLocator):
 def openio(path, mode='r', buffering=-1):
     # allow '-' for stdin/stdout
     if path == '-':
-        if mode == 'r':
+        if 'r' in mode:
             return os.fdopen(os.dup(sys.stdin.fileno()), mode, buffering)
         else:
             return os.fdopen(os.dup(sys.stdout.fileno()), mode, buffering)