Fix unavailable demo course about pages

Demo course about pages were not available (and probably many other
pages as well) because the preview url was the same as the real url.

Kudos to @dannielarriola for solving this!

Close issues #11 #7.

Makefile

@@ -45,7 +45,6 @@ stop:
 
 import-demo-course:
 	$(DOCKER_COMPOSE_RUN_CMS) /bin/bash -c "git clone https://github.com/edx/edx-demo-course ../edx-demo-course && git -C ../edx-demo-course checkout open-release/ginkgo.master && python ./manage.py cms import ../data ../edx-demo-course"
-	# Seed the course permissions: is it necessary? "./manage.py lms seed_permissions_roles 'course-v1:edX+DemoX+Demo_Course'"
 
 create-staff-user:
 	$(DOCKER_COMPOSE_RUN_LMS) /bin/bash -c "./manage.py lms manage_user --superuser --staff ${USERNAME} ${EMAIL} && ./manage.py lms changepassword ${USERNAME}"

nginx/config/templates/lms.conf.templ

@@ -1,6 +1,6 @@
 server {
   listen 80;
-  server_name £{LMS_HOST};
+  server_name £{LMS_HOST} preview.£{LMS_HOST};
   
   # Prevent invalid display courseware in IE 10+ with high privacy settings
   add_header P3P 'CP="Open edX does not have a P3P policy."';

openedx/config/templates/cms.env.json.templ

@@ -6,7 +6,7 @@
   "OAUTH_OIDC_ISSUER": "http://localhost:8000/oauth2",
   "PLATFORM_NAME": "${PLATFORM_NAME}",
   "FEATURES": {
-    "PREVIEW_LMS_BASE": "${LMS_HOST}"
+    "PREVIEW_LMS_BASE": "preview.${LMS_HOST}"
   },
   "LMS_ROOT_URL": "http://${LMS_HOST}",
   "CMS_ROOT_URL": "http://${CMS_HOST}",

openedx/config/templates/lms.env.json.templ

@@ -6,7 +6,7 @@
   "OAUTH_OIDC_ISSUER": "http://localhost:8000/oauth2",
   "PLATFORM_NAME": "${PLATFORM_NAME}",
   "FEATURES": {
-    "PREVIEW_LMS_BASE": "${LMS_HOST}"
+    "PREVIEW_LMS_BASE": "preview.${LMS_HOST}"
   },
   "LMS_ROOT_URL": "http://${LMS_HOST}",
   "CMS_ROOT_URL": "http://${CMS_HOST}",