Add official support for arduino-pico/rp2040. (#33)

This fixes #32.

.github/workflows/compile-examples.yml

@@ -70,6 +70,14 @@ jobs:
             platforms: |
               - name: esp32:esp32
                 source-url: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
+          - fqbn: rp2040:rp2040:arduino_nano_connect
+            platforms: |
+              - name: rp2040:rp2040
+                source-url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+          - fqbn: rp2040:rp2040:rpipico
+            platforms: |
+              - name: rp2040:rp2040
+                source-url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
 
     steps:
       - name: Checkout

README.md

@@ -18,6 +18,7 @@ This library works for
 * [ArduinoCore-samd](https://github.com/arduino/ArduinoCore-samd): [`Arduino Zero`](https://store.arduino.cc/arduino-zero), [`MKR 1000`](https://store.arduino.cc/arduino-mkr1000-wifi), [`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`MKR GSM 1400`](https://store.arduino.cc/arduino-mkr-gsm-1400-1415), [`MKR NB 1500`](https://store.arduino.cc/arduino-mkr-nb-1500-1413), [`MKR WAN 1300/1310`](https://store.arduino.cc/mkr-wan-1310) :heavy_check_mark:
 * [ArduinoCore-mbed](https://github.com/arduino/ArduinoCore-mbed): [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano 33 BLE`](https://store.arduino.cc/arduino-nano-33-ble), [`Nano RP2040 Connect`](https://store.arduino.cc/nano-rp2040-connect), [`Edge Control`](https://store.arduino.cc/edge-control) :heavy_check_mark:
 * [arduino-esp32](https://github.com/espressif/arduino-esp32): `ESP32 Dev Module`, `ESP32 Wrover Module`, ... :heavy_check_mark:
+* [arduino-pico](https://github.com/earlephilhower/arduino-pico): [`Raspberry Pi Pico`](https://www.raspberrypi.org/products/raspberry-pi-pico), `Adafruit Feather RP2040`, ... :heavy_check_mark:
 
 ## Example
 ```C++

library.properties

@@ -6,5 +6,5 @@ sentence=Arduino library for providing convenient macros for printf-style debugg
 paragraph=
 category=Other
 url=https://github.com/107-systems/107-Arduino-Debug
-architectures=samd,esp32,mbed,mbed_nano,mbed_portenta,mbed_edge
+architectures=samd,esp32,mbed,mbed_nano,mbed_portenta,mbed_edge,rp2040
 includes=107-Arduino-Debug.hpp