- Added function R3MYSQL_set_autocommit to enable/disable autocommit.

In R3MYSQL_connect:

- added mysql_options ( conn, MYSQL_OPT_RECONNECT, (const void *) "1" ) to enable automatic reconnect;
- added mysql_autocommit ( conn, 1 ) to enable autocommit by default.

In R3MYSQL_fetch_row:

- replaced strlen with mysql_fetch_lengths to get the correct field lengths, even in case of a binary field;
- added the test if a field is NULL to return a none value.
- Added int-set-autocommit command.
- Added the autocommit attribute to the database object.
- Added the set-autocommit method to the database object.
- Added the "created" column to the "addressbook" table.
- Added some more rows to the "addressbook" table to test for NULL and empty values.
- Added the test for the set-autocommit method.