Fix use of const in test suite for node 0.12
Fix use of const in test suite for node 0.12

statyan/knex,carragom/knex,noodle/knex,carragom/knex,statyan/knex,WaltRock/knex,tgriesser/knex,Atlantis-Software/knex,noodle/knex,abegines/knex,CorvusCorrax/knex,wubzz/knex,WaltRock/knex,tgriesser/knex,wubzz/knex,Atlantis-Software/knex,CorvusCorrax/knex,abegines/knex,tgriesser/knex