Compress static files after customizations

The previous behavior compressed files, then customized the horizon
install. By doing this, static files in the customization modules were
left out of the static collection/compression process. This change in
ordering will now catch those files.

Additionally, a notification is sent to the apache restart handler.

Change-Id: I5c6678c2ef93b46f38cf94f19c9b2cf444411ea8
Closes-Bug: #1598146

releasenotes/notes/compress-customization-a7d03162d837085f.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - The standard collectstatic and compression process in the os_horizon role
+    now happens after horizon customizations are installed, so that all static
+    resources will be collected and compressed.

tasks/horizon_post_install.yml

@@ -77,18 +77,6 @@
   tags:
     - horizon-configs
 
-- name: Collect and compress static files
-  command: "{{ item }}"
-  become: yes
-  become_user: "{{ horizon_system_user_name }}"
-  with_items:
-    - "{{ horizon_bin }}/horizon-manage.py collectstatic --noinput"
-    - "{{ horizon_bin }}/horizon-manage.py compress --force"
-  tags:
-    - horizon-configs
-    - horizon-static-collect
-    - horizon-command-bin
-
 - name: Setup Horizon config(s)
   template:
     src: "{{ item.src }}"
@@ -124,3 +112,16 @@
   when: horizon_customization_module is defined
   tags:
     - horizon-configs
+
+- name: Collect and compress static files
+  command: "{{ item }}"
+  become: yes
+  become_user: "{{ horizon_system_user_name }}"
+  with_items:
+    - "{{ horizon_bin }}/horizon-manage.py collectstatic --noinput"
+    - "{{ horizon_bin }}/horizon-manage.py compress --force"
+  notify: Restart apache2
+  tags:
+    - horizon-configs
+    - horizon-static-collect
+    - horizon-command-bin