Add brake by wire

[wheitman]

• [x] Add hardware (e.g. linear actuator) to brake pedals
• [ ] Write hardware to either OBC or MCU
• [ ] Write low-level ROS node to interface with hardware

[wheitman]

@SashaLuich has mounted the linear actuator, though they still need to be wired. We can use @ashwin-som 's EPAS node as a good starting piont for this node, as they both run through CANables.