PHP 5.3 builds are failing (and are running with outdated distro config)

[sampart]

Example: https://travis-ci.org/whiteoctober/WhiteOctoberPagerfantaBundle/jobs/324420688

First issue:

This job ran on our Precise environment, which is in the process of being decommissioned. Please read about the status of the rollout on the blog, and take note that you can explicitly stay on Precise by specifying dist: precise in your .travis.yml.

Second issue:

 - Installing pagerfanta/pagerfanta (v1.0.5): Downloading (100%)
    proc_open(): fork failed - Cannot allocate memory
    The archive may contain identical file names with different capitalization (which fails on case insensitive filesystems)
    Unzip with unzip command failed, falling back to ZipArchive class
The following exception is caused by a lack of memory or swap, or not having swap configured
Check https://getcomposer.org/doc/articles/troubleshooting.md#proc-open-fork-failed-errors for details
PHP Warning:  proc_open(): fork failed - Cannot allocate memory in phar:///home/travis/.phpenv/versions/5.3.29/bin/composer/vendor/symfony/console/Application.php on line 979

You can see from the log that composer is an outdated version, and xdebug is enabled. Disabling xdebug (which newer composers will do) would probably sort this.

[sampart]

This issue is superseded by #193, but I'm going to leave it open for now.