Create example for ibus on RP2040

[gandy92]

This commit adds an example how to use an ibus receiver with a RP2040 mcu.

Related Issue

As discussed here

Description

The example code includes a working minimal platformio.ini in form of a comment.

Type of PR

• Bug fix
• Feature enhancement
• Documentation update
• Other (specify): _______________

Checklist:

• I have performed a self-review of my code
• I have read and followed the Contribution Guidelines.
• I have tested the changes thoroughly before submitting this pull request.
• I have provided relevant issue numbers, screenshots, and videos after making the changes.
• I have commented my code, particularly in hard-to-understand areas.

[Witty-Wizard]

change the file name here to ibus_basic.ino

[Witty-Wizard]

@gandy92, is there a pre compiler directive to identify the earlphile core for rp2040 we can use it to isolate the invert function, or maybe directly use the rp2040 API for implementing uart inversion

[Witty-Wizard]

@gandy92 I have added a .arduino-ci.yml file to build the example for earlephile core, this should not cause conflict when releasing the library in the arduino library manager