Helping with MacPorts documentation

[Jim Busser]

> 5.3.7.1. Configure Universal
> 
> http://guide.macports.org/#reference.phases.configure.universal
> 
> Universal keywords are used to make a port compile on the Mac OS X platform to run on both PPC and Intel processors.

As Universal keywords are used for more than just the above, could it better acknowledge the more general case (and, over time, should PPC and Intel be reversed as PPC shrinks in recency and usage) thusly?

	... platform to support more than one mode (e.g. 32-bit, 64-bit) and/or to run on both Intel and PPC processors.