Delete netcode

src/Makefile

src/Makefile.d/features.mk

src/Makefile.d/win32.mk

src/d_clisrv.c

src/d_clisrv.h

src/d_net.c

src/d_net.h

src/d_netcmd.c

src/d_netfil.c

src/d_netfil.h

src/deh_tables.c

src/doomdef.h

src/hu_stuff.c

src/i_tcp.c

src/m_menu.c

src/m_menu.h

src/mserv.c

src/sdl/i_system.c