add better condition check for rake

Rakefile

@@ -1,11 +1,12 @@
 namespace :db do
   env = ENV["RAILS_ENV"]
-  fail "Cannot run rake db:create in production." if env == 'production'
+  if env != 'production'
     desc "Create and migrate the #{env} database"
     task :create do
       sh "createdb travis_#{env}" rescue nil
       sh "psql -q travis_#{env} < #{Gem.loaded_specs['travis-migrations'].full_gem_path}/db/structure.sql"
     end
+  end
 end
 
 desc "generate gemspec"