backport transport_tcp bugfix to Kinetic

[andyli]

Here I cherrypicked the fix in #1050 and applied it to the kinetic-devel branch.
Tested on my machine in WSL:

rosrun turtlesim turtle_teleop_key
rostopic echo /turtle1/cmd_vel

Everything works as expected.

---

For people who want to get this now:

git clone -b transport_tcp_kinetic https://github.com/andyli/ros_comm.git
ln -s /abs/path/to/ros_comm ~/catkin_ws
cd ~/catkin_ws
catkin_make
catkin_make install

# you may add this line to ~/.bashrc
source ~/catkin_ws/devel/setup.bash

[dirk-thomas]

Thank you. But all backports will happen before the next Kinetic release in a single pull request (similar to e.g. #1008). Therefore I will close this for now.