Added first experimental implementation of data-centric view in Active Elements slideout.
Work in prorgress on entities.js.
Added rendering timeout of ten seconds to avoid endless rendering loops due to
unlimited queries in large databases.
Merge branch 'develop' into active_elements
Merge branch 'develop' of github.com:/structr/structr into develop
Merge branch 'develop' into active_elements
Added more inclusion conditions for active elements.