Increase default timeout on CI
Increase default timeout on CI

This failure https://travis-ci.org/jonleighton/spring/jobs/6857030 has
the expected stdout, yet it got a timeout error, so I wonder if Travis
was just being slow and it hit the timeout. To be sure, use a longer
timeout on the CI.

grosser/spring,ypresto/spring,y-yagi/spring,universsky/spring-1,maclover7/spring,mariusbutuc/spring,pigoz/spring,rails/spring,smathy/spring,slobodankovacevic/spring