Update README and docs with PyPI installation

Author: ravinkohli

README.md

@@ -41,6 +41,14 @@ Then API starts the following procedures:
 
 ## Installation
 
+### PyPI Installation
+
+```sh
+
+pip install autoPyTorch
+
+```
+
 ### Manual Installation
 
 We recommend using Anaconda for developing as follows:

docs/installation.rst

@@ -11,14 +11,23 @@ System requirements
 
 Auto-PyTorch has the following system requirements:
 
-* Linux operating system (for example Ubuntu), Mac OS X `(get Linux here) <https://www.wikihow.com/Install-Linux>`_,
+* Linux operating system (for example Ubuntu) `(get Linux here) <https://www.wikihow.com/Install-Linux>`_,
 * Python (>=3.6) `(get Python here) <https://www.python.org/downloads/>`_.
 * C++ compiler (with C++11 supports) `(get GCC here) <https://www.tutorialspoint.com/How-to-Install-Cplusplus-Compiler-on-Linux>`_ and
 * SWIG (version 3.0.* is required; >=4.0.0 is not supported) `(get SWIG here) <http://www.swig.org/survey.html>`_.
 
 Installing Auto-Pytorch
 =======================
 
+PyPI Installation
+-----------------
+
+.. code:: bash
+    pip install autoPyTorch
+
+Manual Installation
+-------------------
+
 .. code:: bash
 
     # Following commands assume the user is in a cloned directory of Auto-Pytorch