Travis: Initiating build for commit '54ce7af6f3fb7f26ab6107e646bef5438196522d' on branch 'master': refs #5144 better fix for array to string to conversion.

Noticed this hack while I worked on the tracker refactoring. Dispatch
should always return a string. Fixing the problem where it actually occurs.
An even better fix would be not to support serialize=0 for format PHP as
it is meant only for internal requests. If someone wants to access data
serialize=1 should be set.