multiple parsers

The SAX parsers that I've designed for modeltools, shell tools and click tools can be used with different schema at different times within a single tool. For instance, modelsolver's parser parses the entire model specification document at launch and then later on can parse in a values image (.Image) document.

But these SAX parsers are not reentrant. And there are a couple of situations where this is an issue (and there may be more situations in the future).

So the solution is to create a second SAX parser for use in these instances. Many of the parser classes can be used in both parsers, but some classes cannot be shared.