Add two more kinds of invalid UTF-8 to generate

As far as I know, this completes the set of possible invalid encodings.

--HG--
extra : rebase_source : 67b2c2d04dd9aa582e4d8d5d0097be1525395c41
extra : amend_source : c88aefbe0c96c6a496c3a74bbf4d17a0a5da0e16
Added tag 1.0.0.1 for changeset 7cba97c86467