32 bitness in the Windows SP

[Rod Widdowson]

I'm playing around with the V3 SP Windows installer and I'm back at the thorny issue of 32 bit support.

The current 64 installer sets up either a 32bit or a 64 bit shibd and if ISAPI is to be installed appears to selectively do a 32 bit
or a 64 bit ISAPI install (which often doesn’t work of course)

In V3 I'm pulling all the ISAPI installation (the dll will still ship) against a one-off configuration (QtExec of an "appcmd" verb)
to set up both the 32 bit and the 64 bit plugins.  That way we can serve either 32 bit or 64 bit app pools.

Empirically and anecdotally the 64 bit shibd works with a 32 bit webserver plugin.

I'd like to push the edge of this envelope slightly in V3 by only every installing the 64 bit service.  We can ship the 32 bit
shibd.exe but leave it as an exercise to the user to swap it in if they want. This cleans up the installer a fair bit and I think it
might clean up the documentation too.

This appears to leave us with two options for support

1) Deal with it like mod_shib1.3 and so on.  "32 bit app pools on a 64 bit machine are unsupported, we still ship what you need and
if it works for you, good on you, if not you might investigate a 32 bit shibd, but then your 64 bit app pools might not work".
Support for a 32 bit Apache on a 64 bit Server would be the same.

2) Do the due diligence to establish whether 64/32 bit Shibd/Webserver thang is OK on Intel-endian architectures.  I wouldn't even
suggest that except that if longer term we are going to think about a different shibd we (I) need to swap in that code.

And of course there is the third option of leaving things as is.  Install the bitness of shibd that the user wants and only install
the webserver dll of that bitness.

Thoughts?