Clarify Kolibri installation / migration requirements, per @benjaoming

roles/kolibri/tasks/main.yml

@@ -25,23 +25,27 @@
     group: root
     mode: 0755
 
+# 2019-10-14: An alternative might be to put KOLIBRI_USER="kolibri" into
+# /etc/kolibri/conf.d/iiab.conf
 - name: Save kolibri_user ({{ kolibri_user }}) to /etc/kolibri/username
   copy:
-    content: "{{ kolibri_user }}"
+    content: "{{ kolibri_user }}"    # i.e. kolibri
     dest: /etc/kolibri/username
     owner: root
     group: root
     mode: 0644
-    
+
+# 2019-10-14: An alternative mentioned by @benjaoming (Benjamin Bach) would be
+# to put KOLIBRI_HOME="/library/kolibri" into /etc/kolibri/conf.d/iiab.conf
 - name: Save kolibri_home (KOLIBRI_HOME="{{ kolibri_home }}") to /etc/kolibri/daemon.conf
   copy:
-    content: 'KOLIBRI_HOME="{{ kolibri_home }}"'
+    content: 'KOLIBRI_HOME="{{ kolibri_home }}"'    # i.e. /library/kolibri
     dest: /etc/kolibri/daemon.conf
     owner: root
     group: root
     mode: 0644
 
-- name: apt install latest Kolibri .deb from {{ kolibri_deb_url }} (populates {{ kolibri_home }}, migrates database)    # i.e. /library/kolibri
+- name: apt install latest Kolibri .deb from {{ kolibri_deb_url }} (populates {{ kolibri_home }} / migrates database, based on params set in /etc/kolibri)
   apt:
     deb: "{{ kolibri_deb_url }}"    # https://learningequality.org/r/kolibri-deb-latest
   environment: