Update win32mbcs extension
* Code cleanup by Matt.
* Fix the issue with case-insensitive fs support
by wrapping also util.fspath() and util.checkcase()
* Abort program when path conversion is failed.
error: pretxncommit.nocommits hook failed: no commits allowed
transaction abort!
rollback completed
abort: no commits allowed
error: pretxncommit.nocommits hook failed: no commits allowed
transaction abort!
rollback completed
abort: no commits allowed