Force travis to create the pgsql test db

.travis.yml

@@ -7,10 +7,9 @@ php:
 
 env:
   - DB=mysql
-  - DB=postgres
 
 before_script:
   - sh -c "if [ '$DB' = 'mysql' ]; then mysql -e 'create database IF NOT EXISTS yiitest;'; fi"
-  - sh -c "if [ '$DB' = 'postgres' ]; then psql -U postgres -c 'drop database if exists yiitest;'; fi"
-  - sh -c "if [ '$DB' = 'postgres' ]; then psql -U postgres -c 'create database yiitest;'; fi"
+  - psql -U postgres -c 'drop database if exists yiitest;'; 
+  - psql -U postgres -c 'create database yiitest;';
 script: phpunit