Update Readme for Graph_mxnet (#503)

* Update Readme

* Update Readme 2

* Update Readme 3

* Update Readme 4

* Update Readme 5

* Update Readme 6

* simplify binary install instructdions

* fix format issue

README.md

@@ -29,14 +29,52 @@ Please see the files `3rdparty/ngraph-mxnet-bridge/ngraph.mk` and `make/config.m
 
 ## Compilation instructions for Ubuntu 16.04
 
-1. **Clone the nGraph-MXNet repository**
+A. **Option 1: Use a pre-built Mxnet package**
+
+1. **Install Ubuntu prerequisites**
+   Run the following commands from a command-line:
+
+     ``` sh
+      sudo apt-get update
+      sudo apt-get install -y \
+       libatlas-base-dev \
+       libopenblas-dev \
+       libopencv-dev\
+       python \
+       python-pip \
+       python3 \
+       python3-pip \
+       virtualenv
+     ```
+1. **(Optional) Activate a Python virtual environment.**
+
+   Activate the Python virtual environment into which you wish
+   to process with ngraph-mxnet bridge installation.
+
+   (Please visit http://python.org for more information on Python virtual
+   environments.)
+
+   For example:
+   ``` sh
+    source ~/path/to/my/venv/bin/activate
+   ```
+
+1.  **Install the pip package.**
+
+   Warning, this package has only been tested on Ubuntu 16.04 with Intel CPUs from the Haswell line and later. Use on other platforms/CPUs may or may not work.
+
+   ``` sh
+    pip install ngraph-mxnet
+   ```
+
+B. **Option 2: Clone the nGraph-MXNet repository**
 
    If you have not already done so, create a clone on the local file system of
    the official nGraph-enabled Apache MXNet repository:
 
-     ``` sh
-     git clone --recursive https://github.com/NervanaSystems/ngraph-mxnet.git
-     ```
+   ``` sh
+      git clone --recursive https://github.com/NervanaSystems/ngraph-mxnet.git
+   ```
 
    In the instructions below, the root directory of the cloned repository shall
    be referred to as `MXNET_ROOT`.
@@ -89,8 +127,7 @@ Please see the files `3rdparty/ngraph-mxnet-bridge/ngraph.mk` and `make/config.m
    ``` sh
    cd MXNET_ROOT
    make USE_NGRAPH=1 USE_CUDA=0 DEBUG=0 -j
-   ```
-
+     ```
 1. **(Optional) Install the MXNet Python bindings**
 
    Once `libmxnet.so` has been built, one can optionally install Python bindings
@@ -172,7 +209,7 @@ This is a temporary limitation expected to be lifted in a future release.
 
 ### Supported nGraph back-ends
 The nGraph library supports a number of backends, including `"CPU"`, `"INTERPETER"`, and `"GPU"`.
-The supported models listed above explicitly use nGraph's `"CPU"` back end, and may not function
+The supported models listed above explicitly use nGraph's `"CPU"` backend, and may not function
 properly if altered to use different nGraph back-ends.
 This is a temporary limitation expected to be lifted in a future release.