Teleinfo "historique" option for RFXtrx433XL batch 4918 and xx19

To install the Teleinfo option PCB on the RFXtrx433XL version 5.1:

1. Open the enclosure by removing the 4 screws.
2. Press the 5 pins of the P1 PCB into the RFXtrx433XL PCB RFXtrx V5.1.
   Use a wrench to push the connector into the PCB until the black part of the Press-Fit connector is on the RFXtrx PCB.
3. Cut a few plastics from the upper side (only the raised edge) of the enclosure for the cable, using a Stanley knife. 
4. Cut also at the same position a few plastics from the raised edge of the bottom part.
5. Close the enclosure. First turn the screw counter clockwise until you hear/feel a soft click, now turn the screw clockwise and fix the screw (not too tight)