Added comments on use_transactional_fixtures
Added comments on use_transactional_fixtures

Added some information to rails_helper.rb to describe why
use_transactional_fixtures is set to false. Specifically, we're using
the database_cleaner gem to handle database management in tests

BOWiki/BOW,EBWiki/EBWiki,BOWiki/BOW,BOWiki/BOW,EBWiki/EBWiki,EBWiki/EBWiki,EBWiki/EBWiki