Network cleanup (#6302)

* Cleanup network headers

* Move peerhandler to a specific header to reduce compilation times
* Move socket.cpp/h to network folder

* More work

* Network code cleanups

* Move socket.{cpp,h} to network folder
* Move Address object to network/address.{cpp,h}
* Move network exceptions to network/networkexceptions.h
* Client: use unique_ptr for Connection
* Server/ClientIface: use shared_ptr for Connection

* Format fixes

* Remove socket.cpp socket.h from clang-format whitelist

* Also fix NetworkPacket code style & make it under clang-format

src/httpfetch.cpp

@@ -17,15 +17,15 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include "socket.h" // for select()
-#include "porting.h" // for sleep_ms(), get_sysinfo(), secure_rand_fill_buf()
 #include "httpfetch.h"
+#include "porting.h" // for sleep_ms(), get_sysinfo(), secure_rand_fill_buf()
 #include <iostream>
 #include <sstream>
 #include <list>
 #include <map>
 #include <cerrno>
 #include <mutex>
+#include "network/socket.h" // for select()
 #include "threading/event.h"
 #include "config.h"
 #include "exceptions.h"