modified: teensy/README.md

Updated teensy/README.md to reflect change in build process (teensyduino is no
longer required for build).

teensy/README.md

-Build Instructions for Teensy 3.1
-
-This assumes that you have TeensyDuino installed and set the ARDUINO environment
-variable pointing to the where Arduino with TeensyDuino is installed.
-
-```
-cd teensy
-ARDUINO=~/arduino-1.0.5 make
-```
-
-To upload micropython to the Teensy 3.1.
-
-Press the Program button on the Teensy 3.1
-```
-make upload
-```
-
-Currently, the python prompt is through the USB serial interface.
+# Build Instructions for Teensy 3.1
+
+Currently the Teensy 3.1 port of Micro Python builds under Linux and not under Windows.
+
+The tool chain required for the build can be found at <https://launchpad.net/gcc-arm-embedded>.
+
+Downlaod the current Linux *.tar.bz2 file. Instructions regarding unpacking the file and moving it to the correct location 
+as well as adding the extracted folders to the enviroment varabe can be found at 
+<http://eliaselectronics.com/stm32f4-tutorials/setting-up-the-stm32f4-arm-development-toolchain/>
+
+## Previous Instructions Shown Below (no longer valid)
+
+This assumes that you have TeensyDuino installed and set the ARDUINO environment
+variable pointing to the where Arduino with TeensyDuino is installed.
+
+```
+cd teensy
+ARDUINO=~/arduino-1.0.5 make
+```
+
+To upload micropython to the Teensy 3.1.
+
+Press the Program button on the Teensy 3.1
+```
+make upload
+```
+
+Currently, the python prompt is through the USB serial interface.