Added instructions for using this add-on with PlatformIO

This will allow people to still use this plugin without having to burn the bootloader, as it allows the user to specify the upload speed

README.md

@@ -1,3 +1,4 @@
+# Sanguino
 #### Developed by Kristian Sloth Lauszus, 2012
 
 The code is released under the GNU General Public License.
@@ -6,7 +7,9 @@ _________
 
 This is a Sanguino third-party hardware add-on for the Arduino IDE.
 
-To use it either use the Arduino board manager and add the following url: <https://raw.githubusercontent.com/Lauszus/Sanguino/master/package_lauszus_sanguino_index.json> or simply create a folder named hardware inside your sketchbook directory. Now move the Sanguino directory inside that folder. The structure would look like this:
+To use this add-on simply add the following url: <https://raw.githubusercontent.com/Lauszus/Sanguino/master/package_lauszus_sanguino_index.json> to the Arduino boards manager. Please see the following page for more information: <https://learn.adafruit.com/add-boards-arduino-v164>.
+
+Advanced users can install the hardware add-on manually by creating a folder named "hardware" inside your sketchbook directory. Now move the Sanguino directory inside that folder. The structure would look like this:
 
 * Arduino/
 	* hardware/
@@ -17,6 +20,29 @@ To use it either use the Arduino board manager and add the following url: <https
 			* README.md
 			* boards.txt
 
+## PlatformIO
+
+It is also possible to use this add-on with [PlatformIO](https://platformio.org/). For instace you can use the Sanguino ATmega644 or ATmega644A running at 16 MHz by creating the following entry in your platformio.ini file:
+
+```ini
+[env:sanguino_atmega644p]
+platform = atmelavr
+framework = arduino
+board = sanguino_atmega644p
+```
+
+This will also allow you to specify the upload speed by adding the following entry:
+
+```ini
+upload_speed = 57600
+```
+
+This is needed if you have not burned the Optiboot bootloader.
+
+The list of boards can be found here: <http://docs.platformio.org/en/latest/platforms/embedded_boards.html#sanguino>.
+
+## ATmega1284
+
 Since the ATmega1284 is not supported by Avrdude. You will have to burn the bootloader manually from the command line. See this file for help: [ATmega1284.md](bootloaders/optiboot/ATmega1284.md).
 
 Also check out the following site for more information: <http://blog.stevemarple.co.uk/2013/01/how-to-use-atmel-atmega1284-non-p.html>.