MainBoardSCH: power switch circuit

Merge branch 'v1.0_schema' of https://github.com/RoboticsBrno/RB3204-RBCX into v1.0_schema

MainBoardSCH: Add connectors for US and Servo + step downs

MainBoard: Rename files from `MainBoard` to `RBCX-MainBoard` - better distinguishing from RBControl files

MainBoardSCH: Add all required peripheries to STM MCU, finish encoder pinouts TODO: - fix motor PWMs output for DRV8833 - add ESP32 connectors - add ultrasonic connectors - add servo connectors

MainBoardSCH: Add first part of schema with STM32F103VCT6

Backlink to CADLAB.io has been added.

README: change name from RB3203 to RB3204 Due to the conflict with BlackBox

Add first part of schema with STM32F103VCT6

Initial commit