handle HUP on any mode socket

I am using libwebsockets on Windows 7 in external poll mode.
I am finding that if I present a socket fd on a normal HTTP connection
(LWS_CONNMODE_HTTP_SERVING:) to libwebsocket_service_fd with just a HUP
event, the event doesn't get handled but revents gets cleared indicating
that the event has been handled.  Should it be handled in the same way
as LWS_CONNMODE_WS_SERVING?

(Modified by AG to apply to all sockets)

Signed-off-by: Andy Green <andy.green@linaro.org>
Signed-off-by: Graham Newton <gnewton@peavey-eu.com>
Drop wsockcompat.h header its not part of msvc

I don't see a wsockcompat.h anywhere in MSVC9 or MSVC8 and their
corresponding sdk's. It does not seem like this is a standard windows
header, so better drop that and add the compat-defines to the same
place that already has other WSA compat defines.
Support _WIN32 in addition to WIN32 define

MSVC8 and MSVC9 set only _WIN32, so support that define as well to be able
to compile libwebsockets with those compilers.
Windows Fix installing the dll

Without a runtime install directory, cmake won't install the dll at
all. Only the import library was installed. So fix that.
Windows Fix include for win32helpers

The installed headers are all in the same directory, so no relative
path possible there. The cmake files already add the win32helpers
directory to the include paths, so this builds just fine.
unixify websock w32.h line endings

Signed-off-by: Andy Green <andy.green@linaro.org>
Windows Fix usage in Windows XP targetting projects

This is important since this stuff is in publicly included headers
and even though the usage of the WSAPoll API is a runtime decision
the public headers may be used in code that needs to build with
_WIN32_WINNT=0x0501 to support WinXP.

When building a project using libwebsockets with that define set
to 0x0501 winsock.h will not define the WSAPOLLFD struct causing that
project to fail to compile.