Update README.rst and add CONTRIBUTING.rst to repo

Change-Id: Iad7fb5999ae5d9e92f91f5904916b4aaa892cf21

CONTRIBUTING.rst

@@ -0,0 +1,16 @@
+If you would like to contribute to the development of OpenStack,
+you must follow the steps in this page:
+
+   http://docs.openstack.org/infra/manual/developers.html
+
+Once those steps have been completed, changes to OpenStack
+should be submitted for review via the Gerrit tool, following
+the workflow documented at:
+
+   http://docs.openstack.org/infra/manual/developers.html#development-workflow
+
+Pull requests submitted through GitHub will be ignored.
+
+Bugs should be filed on Launchpad, not GitHub:
+
+   https://bugs.launchpad.net/python-tackerclient

README.rst

@@ -7,4 +7,48 @@ Team and repository tags
 
 .. Change things from this point on
 
-This is the client API library for Tacker.
+NFV Orchestration (Tacker) Client
+=================================
+
+CLI and Client Library for OpenStack Tacker
+
+Installation
+============
+
+**Note:** The paths we are using for configuration files in these steps
+are with reference to Ubuntu Operating System. The paths may vary for
+other Operating Systems.
+
+The branch_name which is used in commands, specify the branch_name
+as stable/<branch> for any stable branch installation. For eg:
+stable/queens, stable/pike. If unspecified the default will be
+master branch.
+
+1. Clone tacker-client repository.
+
+  ::
+
+    cd ~/
+    git clone https://github.com/openstack/python-tackerclient -b <branch_name>
+
+
+2. Install tacker-client.
+
+  ::
+
+    cd python-tackerclient
+    sudo python setup.py install
+
+
+You can also install the latest version by using following command:
+
+  ::
+
+    pip install python-tackerclient
+
+
+More Information
+================
+
+[1] Tacker Documentation: https://docs.openstack.org/tacker/
+[2] Tacker Wiki: https://wiki.openstack.org/wiki/Tacker