Improve the README.rst by adding a quick install/using guide.

README.rst

 pyrocksdb
 =========
 
-Python bindings for RocksDB. See http://pyrocksdb.readthedocs.org for details
+Python bindings for RocksDB.
+See http://pyrocksdb.readthedocs.org for a more comprehensive install and usage description.
+
+
+Quick Install
+-------------
+
+Quick install for debian/ubuntu like linux distributions.
+
+.. code-block:: bash
+
+    $ apt-get install build-essential libsnappy-dev zlib1g-dev libbz2-dev libgflags-dev
+    $ git clone https://github.com/facebook/rocksdb.git
+    $ cd rocksdb
+    $ make shared_lib
+    $ export CPLUS_INCLUDE_PATH=${CPLUS_INCLUDE_PATH}:`pwd`/include
+    $ export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:`pwd`
+    $ export LIBRARY_PATH=${LIBRARY_PATH}:`pwd`
+
+    $ cd ../
+    $ apt-get install python-virtualenv python-dev
+    $ virtualenv pyrocks_test
+    $ cd pyrocks_test
+    $ . bin/active
+    $ pip install pyrocksdb
+
+
+Quick Usage Guide
+-----------------
+
+.. code-block:: pycon
+
+    >>> import rocksdb
+    >>> db = rocksdb.DB("test.db", rocksdb.Options(create_if_missing=True))
+    >>> db.put(b'a', b'data')
+    >>> print db.get(b'a')
+    b'data'