Add support for travis on the database

Author: mariochavez

.travis.yml

@@ -1,3 +1,6 @@
 language: ruby
 rvm:
   - ruby-head
+
+before_script:
+  - psql -c 'create database community_test;' -U postgres

config/database.yml

@@ -11,6 +11,7 @@ test:
   database: community_test
   pool: 5
   host: localhost
+  username: <%= ENV['TRAVIS'] ? 'postgres' : '' %>
 
 production:
   adapter: postgresql