Catastrophic backtracking issue in QueryFormatter

There's a catastrophic backtracking regex issue that reproduces easily when there are too many newlines in the SQL file (as they match both the `\s` and `\n` in the `(\s|\n)+` and result in exponential backtracking).
Because of this, having too many consecutive newlines in any part of a SQL file results in never-ending formatting.

Reproduction and fix is in #6.

Start by locating QueryFormatter and the `(\s|\n)+` expression described in the issue. Review the reproduction and fix referenced in issue #6, then verify that SQL containing many consecutive newlines formats promptly without catastrophic backtracking.

Scritto dal modello di indicizzazione a partire dal testo della issue.