Refacto API

[Hpn4]

• [x] Delete all callback in the API related to GUI and the fn_end_vector_ in the pipe.
• [x] Make the ImportType enum in the UserInterfaceDescriptor a new setting.
• [x] Create GUI.cc and GUI.hh that will be a GUI API.
• [ ] Move all GUI logic from API to the GUI API.
• [ ] Delete subscribers in LightUI and call directly function.
• [ ] Move all logic in all Panels (bound check, other api call) to the API.
• [ ] Add error check in API setter (z cannot be < 0 or > time_transformation_size, ...).
• [ ] Split the implementation of API in multiple files (create a folder api and multiple files that include API.hh).