[base] Queue: adds move semantics to queue items
[base] ServerSocket: use unique_ptr for new client socket
[http] HttpWorker: fixes signed vs unsigned comparison in 413 content length check
cleanup
[http] HttpConnection: code cleanup
[http] HttpConnection: code cleanup (use std::function<> over raw fn ptr for client-abort callback)
fixes a php warning
[http] HttpConnection: favor unique_ptr<> for response write chunks