Refactor switch names in code to be more consistent with Shield's port names #8
Description
Currently, the variables and constants referring to switch events have names that are inconsistent with the corresponding ports on the Tecla Shield. Thus, all the names of relevant constants and variables should be changed. Suggestions include:
- SP1 and SP2 (as in Switch Port 1/2) instead of E1/E2
- ECU1 to ECU4 instead of J1 to J4