README: update to include Linux instructions

Add links to prebuilt binaries and Linux build instructions.

Reflow long lines.

Author: Jianchun Xu

README.md

@@ -1,37 +1,55 @@
 Node.js on ChakraCore
-===
-This project enables Node.js to optionally use the ChakraCore JavaScript engine. This project is still **work in progress** and not an officially supported Node.js branch. Please refer to the original [PR](https://github.com/nodejs/node/pull/4765).
+=====================
+
+This project enables Node.js to optionally use the ChakraCore JavaScript
+engine. This project is still **work in progress** and not an officially
+supported Node.js branch. Please refer to the original
+[PR] (https://github.com/nodejs/node/pull/4765).
 
 ### How it works
 
-To enable building and running Node.js with the ChakraCore JavaScript engine, a V8 API shim (ChakraShim) is created on top of the ChakraCore runtime hosting API ([JSRT]
-(https://msdn.microsoft.com/en-us/library/dn249673(v=vs.94).aspx)). ChakraShim implements the most essential V8 APIs so that the underlying JavaScript engine change is transparent to Node.js and other native addon modules written for V8.
+To enable building and running Node.js with the ChakraCore JavaScript engine, a
+V8 API shim (ChakraShim) is created on top of the ChakraCore runtime hosting API
+([JSRT] (https://msdn.microsoft.com/en-us/library/dn249673(v=vs.94).aspx)).
+ChakraShim implements the most essential V8 APIs so that the underlying
+JavaScript engine change is transparent to Node.js and other native addon
+modules written for V8.
 
-A rebuild node.exe and native addon modules with ChakraCore is required for this to work.
+A rebuild of node and native addon modules with ChakraCore is required for this
+to work.
 
 ### Issues
-Please report all issues related to Node-ChakraCore on this separate [issue page](https://github.com/nodejs/node-chakracore/issues).
 
-### Windows
+Please report all issues related to Node-ChakraCore on this separate
+[issue page] (https://github.com/nodejs/node-chakracore/issues).
+
+### Prebuilt Node-ChakraCore binaries
+
+You can download and install prebuilt Node-ChakraCore from the releases page.
+Currently available for:
 
-#### Prebuilt Node binaries
-You can download and install prebuilt Node-ChakraCore from [here](https://github.com/nodejs/node-chakracore/releases).
+* Windows 7+: [here] (https://aka.ms/node-chakracore-release-windows)
+* Ubuntu 16.04 LTS x64:
+  [preview here] (https://aka.ms/node-chakracore-release-linux)
 
-#### How to build
-If you are looking to build this yourself. Here's what you will need.
+### Building Node-ChakraCore
+
+If you are looking to build this yourself, here's what you will need.
+
+#### Windows
 
 Prerequisites:
 * Windows 7 SP1 or higher (Windows 8.1 or higher for ARM builds)
-* [Python 2.6 or 2.7](https://www.python.org)
-* [Visual
-Studio](https://www.visualstudio.com/en-us/downloads/download-visual-studio-vs.aspx)
+* [Python 2.6 or 2.7] (https://www.python.org)
+* [Visual Studio]
+  (https://www.visualstudio.com/en-us/downloads/download-visual-studio-vs.aspx)
 
 Build Command:
 ```batch
 vcbuild chakracore nosign [x86|x64|arm]
 ```
 
-#### How to test
+To run unit tests
 
 ```batch
 vcbuild chakracore nobuild test [x86|x64|arm]
@@ -44,28 +62,42 @@ C:\>node -e "console.log('Hello from Node.js ' + process.jsEngine)"
 Hello from Node.js chakracore
 ```
 
-### Linux
+#### Linux
 
-NOTE: This is work in progress and contents are subject to change.
+Prerequisites:
+* Ubuntu 16.04 LTS x64
 
-The build and test steps are similar to official node.js, with a few
-customizations to build and run with chakracore.
+Install building tools and ChakraCore dependencies:
 
-#### How to build
+```
+sudo apt-get install -y build-essential cmake clang uuid-dev libunwind-dev libicu-dev liblttng-ust-dev
+```
+
+Clone this repo and check out `xplat` branch:
 
 ```
-configure --engine=chakracore
-make
+git clone https://github.com/nodejs/node-chakracore.git
+cd node-chakracore
+git checkout xplat
 ```
 
-#### How to test
+Build:
 
 ```
-$ node -e "console.log('Hello from Node.js ' + process.jsEngine)"
-Hello from Node.js chakracore
+./configure --engine=chakracore
+make
+[sudo] make install
 ```
 
 To run unit tests:
+
 ```
 $ make test
 ```
+
+To test if Node.js was built correctly with ChakraCore:
+
+```
+$ node -e "console.log('Hello from Node.js ' + process.jsEngine)"
+Hello from Node.js chakracore
+```