Add offline config to nginx

So that I can easily switch to it next time I need it. Disabled by default.

Change-Id: I65774ee6b34e5d57c715458a6bc9cfdab1d28d98
Remove setting which is the default value

Change-Id: I79c32aeed6f79b8e734ff625b526876d79aae004
Merge "Remove setting which is the default value"
Merge "Add offline config to nginx"