Update CHANGELOG for v1.0.0

***NO_CI***

Author: nfbot

CHANGELOG.md

@@ -2,7 +2,15 @@
 
 ## [**Changes available only in 'Preview' NuGet packages:**](https://github.com/nanoframework/lib-System.Device.Gpio/tree/HEAD)
 
-[Full Changelog](https://github.com/nanoframework/lib-System.Device.Gpio/compare/v1.0.0-preview.26...HEAD)
+[Full Changelog](https://github.com/nanoframework/lib-System.Device.Gpio/compare/v1.0.0-preview.29...HEAD)
+
+**Documentation and other chores:**
+
+- Update 2 NuGet dependencies [\#18](https://github.com/nanoframework/lib-System.Device.Gpio/pull/18)
+
+## [v1.0.0-preview.29](https://github.com/nanoframework/lib-System.Device.Gpio/tree/v1.0.0-preview.29) (2021-03-02)
+
+[Full Changelog](https://github.com/nanoframework/lib-System.Device.Gpio/compare/v1.0.0-preview.26...v1.0.0-preview.29)
 
 **Documentation and other chores:**