Improve the relevance support on postgress.
Improve the relevance support on postgress.

Add different weights to each column.
Join the results whit the ILIE since the FULLTEXT looks for the exact phrase only.

Signed-off-by: Gustavo Solt <dcf957f3d58f8a2fb62648b31683ed9d94fd71e7@mayflower.de>

brianjking/phpMyFAQ,rogeriopradoj/phpMyFAQ-vagrant,Chris--A/phpMyFAQ,brianjking/phpMyFAQ,brianjking/phpMyFAQ,thorsten/phpMyFAQ,thorsten/phpMyFAQ,thorsten/phpMyFAQ,rogeriopradoj/phpMyFAQ-vagrant,Chris--A/phpMyFAQ,rogeriopradoj/phpMyFAQ-vagrant,Chris--A/phpMyFAQ,brianjking/phpMyFAQ,Chris--A/phpMyFAQ,rogeriopradoj/phpMyFAQ-vagrant,thorsten/phpMyFAQ