add lwIP TCP/IP stack as a runtime driver, native socket syscalls, SysGetMemoryStatus replacing CatchAllDebugBucket, fix timeGetTime to return milliseconds, fix SysSleep to interpret argument as milliseconds, SysGetTick now returns microseconds, harden all syscalls against bad user pointers with CopyFromUser/CopyToUser/MmProbeUser throughout, add networking test apps, port-forward 8080 in runa.bat, split LWIP_DRIVER_CFLAGS, add settings.ini to deploy, remove ethernet.c stub

code/third_party/lwip/FILES

@@ -0,0 +1,6 @@
+contrib/  - lwIP examples, ports, and small apps (formerly http://git.savannah.gnu.org/cgit/lwip/lwip-contrib.git/)
+src/      - The source code for the lwIP TCP/IP stack.
+doc/      - The documentation for lwIP.
+test/     - Some code to test whether the sources do what they should.
+
+See also the FILES file in each subdirectory.