X carriage - bottom plate update

1. Mounting holes for endstop switches are 1mm further apart than in original part. I could not fit it without this change using Omron switches.
2. Mounting holes for endstop switches have 2.2mm diameter instead of 2mm (intended for 2.4mm screwes).
3. Space for the screwhead was changed to conical - less material is taken from thin arch and it better fits screwes from the aliexpress kit that have conical heads.
4. Space for endstop switch is 6.5mm high (like all my switches) instead of 6mm, T