allow cccam reader with ccckeepalive enabled to disconnect by inactivitytimeout

= Reason for enhancement Currently if we set a cccam reader for example with ccckeepalive=1 and inactivitytimeout=600, that reader will remain connected forever and not disconnect after 600sec as defined, only if we disable ccckeepalive it will disconnect by inactivitytimeout. I think it would be a better behavior if the inactivitytimeout ignores the keepalive traffic and still disconnects the reader when no real requests made after the defined inactivitytimeout time.

Ok, if I want it to disconnect why don't I just disable ccckeepalive? Because server on the other side may have a very small inactivitytimeout (example 30sec), then I would expect that enabling ccckeepalive at my side would allow me to not be killed by the server timeout, but still disconnect when reaching my reader inactivitytimeout setting.

= Possible impacts on other features It would allow inactivitytimeout to just work when ccckeepalive is enabled... we should also be able to set inactivitytimeout to 0 if we just don't want it to disconnect at all (i.e. to have the current behavior). Also would be nice if we could also be able to set it to -1 to auto-reconnect on network failure (like for newcamd readers), currently it is not possible for cccam readers.