Made ORMPurger::PURGE_MODE_TRUNCATE  default for ORM purger
added ORMPurger::PURGE_MODE_TRUNCATE as default purge mode for doctrine ORM  load fixtures in webTestCase
combined if conditions in one statement
Merge pull request #98 from vishalmelmatti/master

added ORMPurger::PURGE_MODE_TRUNCATE as default purge mode for doctrine orm load fixtures