Add documentation on how to run tests

Added a testing page to the documentation.

This includes information on:
 * Running PEP8 checks
 * Running unit tests
 * Running functional tests

Closes-bug:#1511731
Change-Id: I4a5cf4be98f32455e36ea7d6a45b18afca043809

doc/source/index.rst

@@ -15,6 +15,7 @@ Contents
    api_v1
    cli
    contributing
+   testing
 
 Indices and tables
 ==================

doc/source/testing.rst

@@ -0,0 +1,67 @@
+.. _testing:
+
+=======
+Testing
+=======
+
+Python Guideline Enforcement
+............................
+
+All code has to pass the pep8 style guideline to merge into OpenStack, to
+validate the code against these guidelines you can run::
+
+    tox -e pep8
+
+Unit Testing
+............
+
+It is strongly encouraged to run the unit tests locally under one or more
+test environments prior to submitting a patch. To run all the recommended
+environments sequentially and pep8 style guideline run::
+
+    tox
+
+You can also selectively pick specific test environments by listing your
+chosen environments after a -e flag::
+
+    tox -e py27,py33,py34,pep8
+
+.. note::
+  Tox sets up virtual environment and installs all necessary dependencies.
+  Sharing the environment with devstack testing is not recommended due to
+  conflicting configuration with system dependencies.
+
+Functional Testing
+..................
+
+Functional testing assumes the existence of the script run_functional.sh in the
+python-ironicclient/tools directory. The script run_functional.sh generates
+test.conf file. To run functional tests just run ./run_functional.sh.
+
+Also, the test.conf file could be created manually or generated from
+environment variables. It assumes the existence of an openstack
+cloud installation along with admin credentials. The test.conf file lives in
+ironicclient/tests/functional/ directory. To run functional tests in that way
+create test.conf manually and run::
+
+    tox -e functional
+
+An example test.conf file::
+
+    [functional]
+    api_version = 1
+    os_auth_url=http://192.168.0.2:5000/v2.0/
+    os_username=admin
+    os_password=admin
+    os_tenant_name=admin
+
+If you are testing ironic in standalone mode, only the parameters
+'auth_strategy', 'os_auth_token' and 'ironic_url' are required;
+all others will be ignored.
+
+An example test.conf file for standalone host::
+
+    [functional]
+    auth_strategy = noauth
+    os_auth_token = fake
+    ironic_url = http://10.0.0.2:6385