docs(readme): update readme with testing info

.travis.yml

@@ -48,7 +48,6 @@ jobs:
         - npm install @commitlint/config-conventional -D
         - npm install @commitlint/travis-cli -D
         - commitlint-travis
-
     # Define the release stage that runs semantic-release
     - stage: release
       language: node_js

docs/README.rst

@@ -1,7 +1,7 @@
 .. _readme:
 
 rkhunter-formula
-==============
+================
 
 |img_travis| |img_sr|
 
@@ -46,13 +46,43 @@ Available states
     :local:
 
 ``rkhunter``
-----------
+------------
 Installs and configures the rkhunter package.
 
 ``rkhunter.package``
-----------
+--------------------
 Installs the rkhunter package.
 
 ``rkhunter.config``
------------------
+-------------------
 This state manages the file ``rkhunter.conf`` under ``/etc`` (template found in "rkhunter/files"). The configuration is populated by values in "rkhunter/map.jinja" based on the package's default values (and RedHat, Debian, Suse and Arch family distribution specific values), which can then be overridden by values of the same name in pillar.
+
+Testing
+-------
+
+Linux testing is done with ``kitchen-salt``.
+
+``kitchen converge``
+^^^^^^^^^^^^^^^^^^^^
+
+Creates the docker instance and runs the ``template`` main state, ready for testing.
+
+``kitchen verify``
+^^^^^^^^^^^^^^^^^^
+
+Runs the ``inspec`` tests on the actual instance.
+
+``kitchen destroy``
+^^^^^^^^^^^^^^^^^^^
+
+Removes the docker instance.
+
+``kitchen test``
+^^^^^^^^^^^^^^^^
+
+Runs all of the stages above in one go: i.e. ``destroy`` + ``converge`` + ``verify`` + ``destroy``.
+
+``kitchen login``
+^^^^^^^^^^^^^^^^^
+
+Gives you SSH access to the instance for manual testing.