python-pyodbc: bump 3.0.6 -> 3.0.7

Changes:
* Added context manager support to Cursor
* Added padding for driver bugs writing an extra byte
* Cursor.executemany now accepts an iterator or generator.
* Compilation improvements for FreeBSD, Cygwin, and OS/X
* Use SQL_DATA_AT_EXEC instead of SQL_DATA_LEN_AT_EXEC when possible for driver compatibility.
* Row objects can now be pickled.