help: there was only a link to the rtd documentation (now directly linked from a "Documentation" navbar entry)
and some duplicate router configuration that was also shown (even with the correct values) when adding a host.
the help page html was not valid due to the values inserted into the router configuration help.
help/documentation policy: add static help to the docs, add dynamic help directly at the places (in the views) where needed
could happen if there once was a IPv6 connection, but now is not any more.
it now kills infos older than 3 minutes from the session.
it also shows the age of the infos now on the hosts overview view (but not on home view due to cosmetic reasons).
optimization: only request the fake images for ipv4/v6 detection if we don't have a fresh IP already.
added example settings for using detectip on (ip6-)localhost
