5.5 and 5.6 support now added to tuning-primer

Written for MySQL Tuning Primer Script by TodoInTX on 2011-05-15

Due to some changes in the way the script evaluates the version number I am able to claim support for all versions >3.23.00. Later versions will automatically be considered supported. Previous versions did not work on MySQL 5.5 and 5.6 before this change. This should fix the problem from occurring again going forward.