Extracted new ErrorMessageRegistry class from Main
Fixed many possible resource leaks

by putting all close() calls in finally blocks
build.xml now reads saxon version from Version class

I think this will work with all versions of saxon >= 9.3, but I only
tested it with Saxon 9.5, so I put it in the saxon95 target.

Also, it requires Ant 1.7.0+ now because of some of the features used.
removed special cases that don't apply
Merge branch 'finally-close' into server branch