Add GPL license, better readme and flash-tool

Setting it up so it's a propper project which can be released. It's
still not showing any temperature and there is no description of
how to set up the hardware yet.

flash.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+luafiles=`find . -name "*.lua" -not -path "./luatool/*"  -exec basename \{} \;`
+
+
+
+for f in $luafiles
+do
+    sudo python2 ./luatool/luatool/luatool.py --port /dev/ttyUSB0 --src $f --dest $f -b 74880 --delay 0.05
+done
+