[add] added maximum client and demo client protection

- default demo clients can no longer be modified/deleted when in demo mode
 - increased default demo reset to 60 minutes

docker-compose.yml

@@ -10,6 +10,8 @@ services:
     environment:
       # set to run app in subdirectory
       RAILS_RELATIVE_URL_ROOT: /rynDNS
+      # set maximum number of clients in db
+      #RAILS_MAX_CLIENTS: 250
       # set custom api key prefix
       #API_KEY_PREFIX: zW3If4s5
       # set custom header name for api key
@@ -19,7 +21,7 @@ services:
       # set app to run as demo
       #RAILS_API_DEMO: 1
       # set cycle to reset demo data
-      #RAILS_DEMO_RESET: 300
+      #RAILS_DEMO_RESET: 60m
     restart: always
     image: ryndns
     container_name: ryndns