Added serialport as parameter to the launch file

Added serialport as parameter to the launch file

Added serialport as parameter to the launch file

Added serialport as parameter to the launch file

 Author:    mayrjohannes <joh.mayr@jku.at>
 Committer: mayrjohannes  <joh.mayr@jku.at>
	modified:   turtlebot_bringup/launch/includes/create/mobile_base.launch.xml
	modified:   turtlebot_bringup/launch/includes/mobile_base.launch.xml
	modified:   turtlebot_bringup/launch/includes/roomba/mobile_base.launch.xml
	modified:   turtlebot_bringup/launch/minimal.launch
Added serialport as parameter to the launch file
Added serialport as parameter to the launch file
Added serialport as parameter to the launch file
Added serialport as parameter to the launch file
Added serialport as parameter to the launch file

	modified:   turtlebot_bringup/launch/includes/kobuki/mobile_base.launch.xml
Merge branch 'hydro-devel' of https://github.com/mayrjohannes/turtlebot into hydro-devel