Add RC5X and Marantz IR protocols

[lutzbuerkle]

I added support for two additional IR protocols to the IR Blaster:

• RC5X: An extension of the RC5 protocol that supports 7 command bits. It uses a single start bit, while the second bit represents the inverted value of the 7th command bit. More details: https://www.sbprojects.net/knowledge/ir/rc5.php
• Marantz: A variant of the RC5X protocol used by certain Marantz devices. After transmitting the address (i.e., the first 8 bits), it introduces a 3.5 ms pause, followed by the 6 command bits and a 6-bit command extension. Reference: https://github.com/Arduino-IRremote/Arduino-IRremote/blob/master/src/ir_RC5_RC6.hpp

Testing

• I verified both protocols using a OnePlus 15 smartphone as the transmitter and an Arduino Uno (with the Arduino-IRremote library) as the receiver
• Additionally, I validated the Marantz protocol with a Marantz Blu-ray player.