Initial commit of Ansible support for the Consul clustering framework (http://consul.io).

Submission includes support for
 - creating and registering services and checks
 - reading, writing and lookup for values in consul's kv store
 - creating and manipulating sessions for distributed locking on values in the kv
 - creating and manipulating ACLs for restricting access to the kv store
 - inventory support that reads the Consul catalog and group nodes according to
     - datacenters
     - exposed services
     - service availability
     - arbitrary groupings from the kv store

This submission makes extensive use of the python-consul library and this is required
as a dependency and can be installed from pip.

The tests were written to target a vagrant cluster which can be setup by following the
instructions here http://github.com/sgargan/consul-vagrant

test/integration/consul.yml

@@ -0,0 +1,82 @@
+- hosts: localhost
+  connection: local
+  gather_facts: false
+
+  vars:
+    # these are the defaults from the consul-vagrant cluster setup
+    - mgmt_token: '4791402A-D875-4C18-8316-E652DBA53B18'
+    - acl_host: '11.0.0.2'
+    - metadata_json: '{"clearance": "top_secret"}'
+
+  pre_tasks:
+    # this works except for the KV_lookusp
+    - name: check that the consul agent is running locally
+      local_action: wait_for port=8500 timeout=5
+      ignore_errors: true
+      register: consul_running
+
+  roles:
+
+    - {role: test_consul_service,
+       when: not consul_running.failed is defined}
+
+    - {role: test_consul_kv,
+       when: not consul_running.failed is defined}
+
+    - {role: test_consul_acl,
+       when: not consul_running.failed is defined}
+
+    - {role: test_consul_session,
+       when: not consul_running.failed is defined}
+
+  tasks:
+
+    - name: setup services with passing check for consul inventory test
+      consul:
+        service_name: nginx
+        service_port: 80
+        script: "sh -c true"
+        interval: 5
+        token: '4791402A-D875-4C18-8316-E652DBA53B18'
+        tags:
+          - dev
+          - master
+
+
+    - name: setup failing service for inventory test
+      consul:
+        service_name: nginx
+        service_port: 443
+        script: "sh -c false"
+        interval: 5
+        tags:
+          - qa
+          - slave
+
+    - name: setup ssh service for inventory test
+      consul:
+        service_name: ssh
+        service_port: 2222
+        script: "sh -c true"
+        interval: 5
+        token: '4791402A-D875-4C18-8316-E652DBA53B18'
+
+    - name: update the Anonymous token to allow anon access to kv store
+      consul_acl:
+        mgmt_token: '{{mgmt_token}}'
+        host: '{{acl_host}}'
+        token: 'anonymous'
+        rules:
+          - key: ''
+            policy: write
+      register: inventory_token
+
+    - name: add metadata for the node through kv_store
+      consul_kv: "key=ansible/metadata/dc1/consul-1 value='{{metadata_json}}'"
+
+    - name: add metadata for the node through kv_store
+      consul_kv: key=ansible/groups/dc1/consul-1 value='a_group, another_group'
+
+    - name: warn that tests are ignored if consul agent is not running
+      debug: msg="A consul agent needs to be running inorder to run the tests. To setup a vagrant cluster for use in testing see http://github.com/sgargan/consul-vagrant"
+      when: consul_running.failed is defined