Increase encoding pre-scan length to 1024, per spec from 2011(!)

51babfe760a1dbe28c4521b2070e692ac872550a was the spec change.

Author: gsnedders

html5lib/inputstream.py

@@ -421,7 +421,7 @@ def __init__(self, source, encoding=None, parseMeta=True, chardet=True):
         # Encoding Information
         # Number of bytes to use when looking for a meta element with
         # encoding information
-        self.numBytesMeta = 512
+        self.numBytesMeta = 1024
         # Number of bytes to use when using detecting encoding using chardet
         self.numBytesChardet = 100
         # Encoding to use if no other information can be found