Hacked support for windows, compile on MinGW for Debian 7
Forgot to end with NULLs
Change macro from DROID_BUILD to ANDROID
This commit provides Windows support

These changes are based on gcc-mingw-w64-i686 (4.6.3-14+8) on Debian Wheezy.
We also use pthreads_win32 project (http://www.sourceware.org/pthreads-win32/)
for pthread support on windows. Makefile can create both isolated binary and
dll for linking on windows.
Adds license to win32_tap.c and win32_tap.h
Forgot to disable ipv6_route for Android
Cleans up compiler warnings with casting
Removes old SVPN_TEST defines
Performs lookup based on subnet_mask for router mode
Cleanup commit
Fixes Windows ARP bug
Fixes errors from improper rebase/merge