Create basic gripper commands

[afonsocastro]

I feel like we should have some shortcuts to be able to close/open the gripper quickly from the command line. Basic command just to open, close, and even request some instant information. All of it from the command line. The open/close command should allow speed control as well.

[Joel-Baptista]

This is a simple approach attempts to solve this issue. It was created alias in .baschrc (image), that execute python srcipts in the use_cases library that connect to the robot, open/close the gripper and disconnect. These alias can be called by anywhere in the terminal and they are not depended in where the project is stored in the machine because it uses "roscd" instead of "cd"