Update CHANGELOG for v1.0.0

***NO_CI***

Author: nfbot

CHANGELOG.md

@@ -2,7 +2,24 @@
 
 ## [**Changes available only in 'Preview' NuGet packages:**](https://github.com/nanoframework/lib-nanoFramework.Graphics/tree/HEAD)
 
-[Full Changelog](https://github.com/nanoframework/lib-nanoFramework.Graphics/compare/v1.0.0-preview.6...HEAD)
+[Full Changelog](https://github.com/nanoframework/lib-nanoFramework.Graphics/compare/v1.0.0-preview.21...HEAD)
+
+**Documentation and other chores:**
+
+- Update dependencies [\#22](https://github.com/nanoframework/lib-nanoFramework.Graphics/pull/22)
+- Update 5 NuGet dependencies [\#20](https://github.com/nanoframework/lib-nanoFramework.Graphics/pull/20)
+
+## [v1.0.0-preview.21](https://github.com/nanoframework/lib-nanoFramework.Graphics/tree/v1.0.0-preview.21) (2020-10-20)
+
+[Full Changelog](https://github.com/nanoframework/lib-nanoFramework.Graphics/compare/v1.0.0-preview.19...v1.0.0-preview.21)
+
+**Documentation and other chores:**
+
+- Update 5 NuGet dependencies [\#19](https://github.com/nanoframework/lib-nanoFramework.Graphics/pull/19)
+
+## [v1.0.0-preview.19](https://github.com/nanoframework/lib-nanoFramework.Graphics/tree/v1.0.0-preview.19) (2020-10-01)
+
+[Full Changelog](https://github.com/nanoframework/lib-nanoFramework.Graphics/compare/v1.0.0-preview.6...v1.0.0-preview.19)
 
 **Documentation and other chores:**