update README for naming changes, fork info

README.md

-# Teensy: development platform for [PlatformIO](http://platformio.org)
-
-[![Build Status](https://github.com/platformio/platform-teensy/workflows/Examples/badge.svg)](https://github.com/platformio/platform-teensy/actions)
-
-Teensy is a complete USB-based microcontroller development system, in a very small footprint, capable of implementing many types of projects. All programming is done via the USB port. No special programmer is needed, only a standard USB cable and a PC or Macintosh with a USB port.
-
-* [Home](http://platformio.org/platforms/teensy) (home page in PlatformIO Platform Registry)
-* [Documentation](http://docs.platformio.org/page/platforms/teensy.html) (advanced usage, packages, boards, frameworks, etc.)
-
-# Usage
-
-1. [Install PlatformIO](http://platformio.org)
-2. Create PlatformIO project and configure a platform option in [platformio.ini](http://docs.platformio.org/page/projectconf.html) file:
-
-## Stable version
-
-```ini
-[env:stable]
-platform = teensy
-board = ...
-...
-```
-
-## Development version
-
-```ini
-[env:development]
-platform = https://github.com/platformio/platform-teensy.git
-board = ...
-...
-```
-
-# Configuration
-
-Please navigate to [documentation](http://docs.platformio.org/page/platforms/teensy.html).
+# Teensy: development platform for [PlatformIO](http://platformio.org)
+
+*fork of https://github.com/platformio/platform-teensy*
+
+Teensy is a complete USB-based microcontroller development system, in a very
+small footprint, capable of implementing many types of projects. All programming
+is done via the USB port. No special programmer is needed, only a standard USB
+cable and a PC or Macintosh with a USB port.
+
+* [Home](http://platformio.org/platforms/teensy) (home page in PlatformIO Platform Registry)
+* [Documentation](http://docs.platformio.org/page/platforms/teensy.html) (advanced usage, packages, boards, frameworks, etc.)
+
+# Usage
+
+1. [Install PlatformIO](http://platformio.org)
+2. Create PlatformIO project and configure a platform option in
+   [platformio.ini](http://docs.platformio.org/page/projectconf.html) file:
+
+## Stable version
+
+```ini
+[env:stable]
+platform = teensy-gcc10
+board = ...
+...
+```
+
+## Development version
+
+```ini
+[env:development]
+platform = https://github.com/thevisus/platform-teensy-gcc10.git
+board = ...
+...
+```
+
+# Configuration
+
+Please navigate to [documentation](http://docs.platformio.org/page/platforms/teensy.html).