Initial AROS support.
The test app doesnt link yet since we are missing a bunch of symbols

but it is a start
AROS: getting closer to link. only a handful of missing symbols now
AROS: it is called IoctlSocket/CloseSocket and WaitSelect on AROS.
Additionally add a aros_init_socket() function to open the bsd socket library and set up networking
AROS more stuff.   The listservers example now compiles and links
it sends packets to the host  but something is still not working.
AROS: we need htons to convert socket port to network order
SOCKADDR_STORAGE: it is called HAVE_SOCKADDR_LEN  not HAVE_SA_LEN
AROS: We have to provide the correct nfds to WaitSelect
When copying the poll() compatibility function from win32 to AROS
we need to update it to set nfds correctly.
While win32 does not care what nfds is set to and works even if nfds is always
0, other platforms, like AROS do care.
AROS: Update README and list AROS as supported and provide build instruction for it
AROS: implement their weird errno handling
AROS: Add copyright boilerplate for aros_compat.c
AROS: add inet_pton emulation and make sure we use recv/send and not read/write
AROS: Add an example for using the SYNC API to AROS
While the ASYNC API is probably always preferable, the SYNC API is easier
to use.  The SYNC API is probably what most users want.
AROS: we dont need to protect aros_compat.c with an ifdef