Adding dynamic_reconfig

Adding Dynamic Reconfiguration

1. In simple terms, Dynamic reconfiguration is a peckage of ROS which allows us to change the values of the parameters and variables during run time.
2. This package is highly useful in terms of pid tuning and in the case, when we are not sure about the value of any variable.
3. In order to do tutorials, a package needs to be created in catkin workspace about which instructions are given in tutorials.
4. Dynamic reconfiguration is already installed while installing ROS on your system.
5. To get started with Dynamic reconfiguration, refer the links to tutorials and summary of the package.

Summary : Dynamic reconfiguration

Tutorials : Dynamic reconfiguration tutorials