More Android/x86 porting

This patch allows all of druntime that is normally compiled to be built without a problem: no asserts will be triggered.  It isn't a complete port of all the headers, just enough to compile.  I had to add posix.arpa.inet to the list of compiled source, because htonl and friends are defined as macros in the bionic headers.  I again removed three unnecessary version(Posix) checks.