Started to implement LogFileCollection
SessionInitiator has an acceptor instead of a socket.
LogFileCollection now holds weak_ptrs to all files that are opened
LogFileCollection is thread safe (via mutex)
LogFile is now thread safe and non-copyable.
Removed unnecessary forward declaration of Session.
Removed unnecessary include of Session.
RealSession now inherits prot::Executor
RealSession::close_file now closes file.
No more dependency on prot::Client in RealSession
RealSession::set_client_info works.
Renamed RealTimestampFactory to DefaultTimestampFactory.
Added ClientHandleFactory
get_timestamp() is now a const member function.
Implemented the DefaultTimestampFactory.