Dynamic wrench application through the GUI

Currently in Gazebo, it is complicated for the user to exert external forces and torques to objects during the simulation. In this project, I will develop tools to allow the user to apply wrenches to objects directly through the GUI. Firstly, I will develop a GUI plugin that allows the user to apply precise forces and torques, such as the one present in Gazebo Classic. Then, I will implement a system that allows the user to exert forces and torques by dragging objects in the scene with the mouse cursor. This goes beyond the kinematic translation and rotation tools currently available, as it will interact with the physics of the models, providing a more convenient interface for the user.