Issue #10740: sqlite3 no longer implicitly commit an open transaction before DDL...

Issue #10740: sqlite3 no longer implicitly commit an open transaction before DDL statements

This commit contains the following commits from ghaering/pysqlite:

* https://github.com/ghaering/pysqlite/commit/f254c534948c41c0ceb8cbabf0d4a2f547754739
* https://github.com/ghaering/pysqlite/commit/796b3afe38cfdac5d7d5ec260826b0a596554631
* https://github.com/ghaering/pysqlite/commit/cae87ee68613697a5f4947b4a0941f59a28da1b6
* https://github.com/ghaering/pysqlite/commit/3567b31bb5e5b226ba006213a9c69dde3f155faf

With the following additions:

* Fixed a refcount error
* Fixed a compiler warning
* Made the string comparison a little more robust
* Added a whatsnew entry