Fix Travis failure
Fix Travis failure

Travis failed because a Ruby 2 API was being called to find the first
character of a string, but the introduction of JMX tests required a
downgrade to Ruby 1.9. This change introduces a 1.9-compatible method
of finding the required character.
pivotalsoftware/session-managers-system-test,pivotalsoftware/session-managers-system-test,pivotalsoftware/session-managers-system-test