security-tracker: cache all json API and feed requests
This also simplifies the request limit configuration as json API and feed requests are cached hence a more strict request limit is not really necessary anymore.
- Configure a uwsgi cache of 1GB for all json API and feed requests
- Cache JSON API and feed requests for 5 minutes
- Use a single global request limit zone
Signed-off-by: Levente Polyak anthraxx@archlinux.org