Boris

Convert to draft, due to some knex troubles with index rebuild ``` Knex: Timeout acquiring a connection. The pool is probably full. Are you missing a transacting(trx) call? ```

The `rebuild` function has been rewritten. It looks like knex only supports one sqlite database connection. I believe the error was caused by multiple knex function calls inside the pipeline....

Thx, I cleaned up the `match-query.js`. Almost all warnings have been fixed. There are still some warnings at the definition of [this.knownLexemes](https://github.com/requarks/wiki/blob/c47e63383e3ec5b026ebde370d09de5fb240fb03/server/modules/search/sqlite3/match-query.js#L124). But I doubt whether it is worth rewriting...