replace *a lot* of file related calls by their GLib counterparts. This is necessary...

replace *a lot* of file related calls by their GLib counterparts. This is necessary for the switch to GTK 2.6 (at least on WIN32).

to do this, I've added file_util.h to wiretap (would file_compat.h be a better name?), and provide compat_macros like eth_open() instead of open(). While at it, move other file related things there, like #include <io.h>, definition of O_BINARY and alike, so it's all in one place.

deleted related things from config.h.win32

As of these massive changes, I'm almost certain that this will break the Unix build. I'll keep an eye on the buildbot so hopefully everything is working again soon.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@16403 f5534014-38df-0310-8fa8-9805f1628bb7