Add build instructions for Linux

Author: me-no-dev

README.md

@@ -2,4 +2,13 @@
 
 This repository contains the scripts that produce the libraries included with esp32-arduino.
 
-Requires: python, make, libncurses-dev, flex, bison and gperf
+Tested on Ubuntu (32 and 64 bit), Raspberry Pi and MacOS.
+
+### Build on Ubuntu and Raspberry Pi
+```bash
+sudo apt-get install git wget curl libssl-dev libncurses-dev flex bison gperf python python-pip python-setuptools python-serial python-click python-cryptography python-future python-pyparsing python-pyelftools cmake ninja-build ccache
+sudo pip install --upgrade pip
+git clone https://github.com/espressif/esp32-arduino-lib-builder
+cd esp32-arduino-lib-builder
+./build.sh
+```