RobotWebTools/roslibjs — pull request #48 by OTL (2013-10-02 12:41:39+00:00)
Title: Add service fail callback

If [this merge request](https://github.com/RobotWebTools/rosbridge_suite/pull/57) is merged, this enable to handle service call failure.
I add another callback for failure handling as an optional argument.

This code works file with older rosbridge, and does not affects for current roslibjs client programs.