Add 'versionfromdb' to opt-in for VERSION() query.
mariadb_native_moodle_database::get_server_info() has been removed
to avoid the specific override: everything is now managed in the base
method which takes care of both MySQL and MariaDB versioning details.
New protected methods have been added too to improve the testing strategy,
allowing to mock the results from an actual DB connection.
The new testing strategy enables simulating even the Azure scenarios.
- Clumsy fallback only when there is no full-text search support
- Mimic solr tests
- pgsql tokenization using simple configuration
- workaround for mysql '*' search issue
- total results proper calculation
- SQL server FTS support
- Standarize dml full-text search checkings
- Upgrade note about the new dml method
- Set search_simpledb as default engine if no solr config
