Current build rules don't accomodate multiple inputs per sample

[alerque]

While most of the time we can hack inputs to use a single file per example, in many cases this is not idiomatic of the way inputs are assumed to be for the various engines. Some split HTML content and CSS styling, others split XML data and XML layout rules, others split content and layout functions is various other ways. We need a way to have more than one input file associated with each example. This probably means splitting each example and engine into it's own directory for clarity, already we're making a mess.