--enable-lsb configure option

I'd like to see a --with-lsb option for configure which
yields an LSB-friendly build configuration.

The full LSB specification is available on the LSB site
(http://www.freestandards.org/spec/), but for our
purposes it mainly just requires installation into /opt
and not assuming the presence of certain libraries.

Essentially:

 - --prefix=/opt

 - statically linking with all C++ libraries (most
aren't guaranteed to be present by LSB, and we also
have to consider C++ ABI issues)

 - statically linking with libgc, and liblcms and any
other libraries which LSB doesn't guarantee the presence of

This is such low-hanging fruit I think it'd be a shame
not to support it. For now, I'm assigning the RFE to
myself so it doesn't get forgotten, but if anyone else
wants to pick it up before I get to it (I've got a pile
of other work to get through), please be my guest.