Keep track of which capability types are used and in use
at the moment for each service.
Update the http debug console to only show services
that have at least one capability type marked as used (this resets upon
restart of the debug console) and show previously used but currently
unused capability types in grey.
Update CapabilityType::mConcurrentConnections based on usage of the
capability type (CT): Each currently in-use CT gets an (approximate)
equal portion of the available number of connections, currently
unused CTs get 1 connection for future use, so that requests can and
will be added to them if they occur. If a CT is currently not in use
but was used before then it's connection (but at most one connection)
is kept in reserve. For example, if there are 8 connections available
and a service served textures and mesh in the past, but currently
there are no texture downloads, then mesh get at most 7 connections,
so that at all times there is a connection available for textures.
When one texture is added, both get 4 connections.
Prepares for throttling number of connections per capability type.
The value is current left at AIPerService::mConcurrectConnections,
so not having an effect yet.
