Removes extra headers
This commit provides Windows support

Code uses SSLIdentity which platform independent. Windows build
does not currently support encryption. Also Windows build links
to ipop-tap dll generated by mingw on Debian.
Windows build uses Schannel for XMPP security.

Since SChannel is native to Windows and does not currently support
DTLS, we only have a secure connection to XMPP server, but the
P2P connections are not encrypted, maybe in future we may look
into IPSec or NSS or OpenSSL for Win32.
Removes libjingle.gyp.diff
Updated API to add support for subnet_mask for router mode
Release allocator to avoid segfault on Windows