Ability to load query with prefixes or base IRI for classes and entities (not necessarily for values)

[tfrancart]

Considering the length of Agent prompts and the length of output queries, it could be desirable to be able to load queries that declare prefixes or base IRI.

Can you:

1. uncomment this part:

2. Also adjust this part:

3. modify queryLoader v13 so that everytime we read a value of rdfType in a TermTypedVariable, it is first checked against the declared prefixes and base, and also the predicate IRI. The logic is kind of similar to this one:

	public boolean usesKnownPrefix(String qname) {
		boolean result = false;
		if(qname.contains(":")) {
			String prefix = qname.substring(0, qname.indexOf(':'));
			result = prefixes.containsKey(prefix);
		}
		return result;
	}
	
	public String uri(String value, boolean fixHttp) {
		// if the value starts with http, return it directly
		if(value.startsWith("http") || value.startsWith("mailto")) {
			// trim the value to remove trailing whitespaces
			return value.trim();
		}
		// if the value uses a known prefix, expand it
		if(usesKnownPrefix(value)) {
			// always trim, trim, trim
			return expand(value).trim();
		}
		
		if(fixHttp) {
			// ... snip ... not interesting here
		} else {
			return null;
		}
	}

We could first do it for classes and predicates, but not necessarily for values.