qt4-mac and qt4-x11

[Michael Dickens]

I dream of some day having a +x11 variant to qt4-mac, but I doubt it
will be fully ABI compatible with the +quartz variant.  So, it might
make sense to keep a qt4-x11 version which is not compatible with the
qt4-mac version at least for now.  I will look into updating qt4-x11 to
the latest release, and I think we should create multiple ports for the
Qt series since 5.0 is coming out soon and we also should have a 4.7.4
version for older OSs (e.g. 10.5 PPC).  Hence, moving to {qt47-mac,
qt48-mac, qt48-x11, qt50-mac} and so forth.  I think these will end up
bring different ports, not subparts, since they will be easier to
maintain that way.  I believe the Qt folks have made 5.0 more modular
for installations, and I'll look into that as an option as well once I
get to that port.  Lots to do on the Qt front; so little time :) - MLD