Text parser rewritten:

Text parser rewritten:
        - supports multibyte encodings
        - more strict rules for lexemes
        - flex isn't used
Add:
        - tsquery plainto_tsquery(text)
          Function makes tsquery from plain text.
        - &&, ||, !! operation for tsquery for combining
          tsquery from it's parts:  'foo & bar' || 'asd' => 'foo & bar | asd'