Disable PHP5.3 In Travis CI config

The default system used for PHP testing on Travis CI does not appear to work for PHP 5.3 (missing package). Until we figure out how to get Travis running correctly (or decide to drop support) we'll comment out 5.3.

Author: bsweeney

.travis.yml

@@ -1,7 +1,7 @@
 language: php
 
 php:
-  - 5.3
+#  - 5.3
   - 5.4
   - 5.5
   - 5.6