Save Isaac from getting emails about failed builds.

Isaac Saito has been working hard to make the Travis CI work with
Kinetic. Removing his email from ravis.yml, to save his inbox from
errors due to other issues.

.travis.yml

@@ -5,11 +5,6 @@ dist: trusty
 language: generic 
 compiler:
   - gcc
-notifications:
-  email:
-    on_failure: always
-    recipients:
-      - [email protected]  # Change this to yours should you copy this file.
 env:
   matrix:
     - USE_DEB=true  ROS_DISTRO="kinetic" ROS_REPOSITORY_PATH=http://packages.ros.org/ros/ubuntu