Switched to xsl:result-document for outputting documents, with exsl:document as a fallback.
Modularizing functions into separate stylesheets: one for XSLT 1.0 exsl funcs, and one for XSLT 2.0 xsl:function funcs.
Local parameterization of some OPF named templates and corresponding xspec tests.
More OPF tests, and default handling added for identifier, title, language, and mod date to ensure EPUB 3 validity.
Tests for OPF metadata with more than one creator/contributor.
Adding skeleton for pending OPF tests.
Refactoring and tests for spine and guide generation for EPUB.
More OPF tests.
Remaining XSpec tests for OPF templates.
Skeletons for NCX tests.
Merge pull request #105 from oreillymedia/forward-compatibility

Forward compatibility with XSLT 2.0 and tests around OPF generation