updating deploy tasks to include nginx for those that include

nginx_site.yml

playbooks/edx-east/deploy_edx_platform.yml

-- name: Configure instance(s)
-  hosts: all
-  sudo: True
-  gather_facts: True
-  vars:
-    openid_workaround: True
-  roles:
-    - edxapp

playbooks/edx-east/deploy_edxapp.yml

@@ -3,4 +3,5 @@
   sudo: True
   gather_facts: True
   roles:
+    - nginx
     - edxapp

playbooks/edx-east/deploy_ora.yml

@@ -3,4 +3,5 @@
   sudo: True
   gather_facts: True
   roles:
+    - nginx
     - ora

playbooks/edx-east/deploy_xqueue.yml

@@ -3,4 +3,5 @@
   sudo: True
   gather_facts: True
   roles:
+    - nginx
     - xqueue