feat: 全量同步 254 个常用的 Arduino 扩展库文件

arduino-libs/arduino-cli/libraries/Rtc_by_Makuna/README.md

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+# Rtc
+
+Arduino Real Time Clock library.  
+An RTC library with deep device support.
+
+[![Donate](https://img.shields.io/badge/paypal-donate-yellow.svg)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=6AA97KE54UJR4)
+
+For quick questions jump on Gitter and ask away.  
+[![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/Makuna/Rtc?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
+
+For bugs, make sure there isn't an active issue and then create one.
+
+## Documentation
+[See Wiki](https://github.com/Makuna/Rtc/wiki)
+
+## Installing This Library (prefered, you just want to use it)
+Open the Library Manager and search for "Rtc by Makuna" and install
+
+## Installing This Library From GitHub (advanced, you want to contribute)
+Create a directory in your Arduino\Library folder named "Rtc"
+Clone (Git) this project into that folder.  
+It should now show up in the import list when you restart Arduino IDE.