The current implementation of the session timeout functionality is not safe to
use. Added a warning to the documentation and disabled the code. If the user
tries to use it, a warning is logged.
The limitation with readconnroute and LONGBLOB is only when data is being sent
from the client to MaxScale. The client can still query for LONGBLOB data
without any side-effects.
The integration of the PCRE2 library into the regexfilter caused the
substitution rules to change now that it actually works and this needed
to be mentioned in the release notes.
Also fixed some minor things like links.
