Moved roles to subdirectory

roles/docker/meta/main.yml

@@ -0,0 +1,3 @@
+---
+dependencies
+  - role: common

roles/docker/tasks/main.yml

@@ -0,0 +1,8 @@
+---
+- name: install docker-compose
+  apt:
+    name: docker-compose
+    state: latest
+    update_cache: yes
+  tags:
+    - docker