Add max autocomplete rows functionality

DBjoin only to start with
Provide addition dbjoin autocomplete option

Search option "words" allows user to type in search words in any order
and we find records which have every word LIKE %word%.

See
http://fabrikar.com/forums/index.php?threads/display-full-list-of-results.35237/
Merge pull request #859 from Sophist-UK/add_autocomplete_max_parameter

Add parameter for max autocomplete rows, provide word searching