* Create new DatabaseSqlite::checkForEnabledSearch() and use it from SearchSqlite...

* Create new DatabaseSqlite::checkForEnabledSearch() and use it from SearchSqlite::fulltextSearchSupported() instead of querying the updatelog table.  This was the only use of updatelog under the non-maint code.
* Add the searchindex table to the list of tables to preserve for testing.
* Adapt SearchEngineTest to work with Sqlite.
* Add fulltext setup for SQLite to the new installer code.
* TODO: SqliteInstaller::setupSearchIndex() should not be using addHtml()