more tests, updated validation and converters (see full commit log)

removed oxygen project descriptor from revision control

nordic html
 * added namespace with prefix "nordic" and URI "http://www.mtm.se/epub/"
 * changed track:Guidelines and track:Supplier to nordic:guidelines and nordic:supplier
 * allowed h1-h6 instead of only h1 in poems etc. (was hd in dtbook)
 * tbody are now required in table; direct tr children are not allowed anymore
 * added cover to schema rule tpb08
 * allowed div for pagebreak
 * rules only relevant for intermediary html: tpb10, tpb12, tpb13
 * simplified tpb14
 * disabled tpb18
 * replaced elements with their html equivalents: linenum, noteref, lic, sent, w, author, bridgehead, byline, covertitle, dateline, docauthor, doctitle, hd, line
 * fixed tpb23, tpb24
 * added MTM and SBS to list of allowed publishers ('TPB', 'MTM', 'SPSM', 'Nota', 'NLB', 'Celia', 'SBS')
 * fixed tpb105 (one of the following classes are now required on pagebreaks: 'page-front', 'page-normal', 'page-special')
 * tpb29: allowed text siblings to block content in "li" elements so that bullets (• ) can be prepended to list items
 * nordic229: sidebars must have either a render-required or a render-optional class
 * nordic246/nordic:247: the element with epub:type="fulltitle" must be a h1 (used for the intermediary html; becomes doctitle in dtbook)
 * nordic248: in the intermediary html, the only allowed content in the main header other than h1 is docauthor and covertitle
 * nordic251: the parent of a lic must be a li
 * nordic254: the aside elements must have one of the following epub:types: 'z3998:production','sidebar','note','annotation','epigraph'

tpb2011-1.sch
 * added MTM and SBS to list of publishers
 * disabled class restriction rules for levels

script: dtbook-to-epub3
 * renamed option from input-dtbook to dtbook
 * added option for discarding or including the intermediary html
 * added option for whether or not validation errors are fatal
 * refactored dtbook-to-epub3.convert.xpl into dtbook-to-html.convert.xpl and html-to-epub3.convert.xpl
 * filename based on 'dtb:uid' in dtbook
 * added cleanup of the generated navigation documents to make sure they conform to the guidelines
 * don't generate id attribute on body element
 * set default bodymatter type to chapter
 * added nordic namespace
 * fixed header content
 * prefix all img src attributes with "images/"
 * fixed image captions. Each dtbook caption element maps to a div element with class "img-caption" inside the html figcaption element
 * fixed some bugs

script: dtbook-validate
 * renamed option from input-dtbook to dtbook
 * added validation of all content documents (including the navigation document)

script: epub3-to-dtbook
 * added option for discarding or including the intermediary html
 * added option for whether or not validation errors are fatal
 * added assertion for navigation document (will throw error)
 * the epub:type "cover" is mapped to the dtbook class "jacketcopy"
 * fixed precedingemptyline
 * the html title element now always becomes meta dc:Title in dtbook, even if there's already a meta dc:title in the html.
 * meta dc:title in html are dropped
 * set dc:Format to DTBook
 * made all dublin core metadata capitalized
 * if there's no render-* class, use render="optional"
 * added 'abbr' class to abbreviations
 * fixed incorrect epub:type "acronym"; should be "z3998:acronym"
 * added 'acronym' class to acronyms
 * added 'bdo' class to bdo
 * fulltitle should only become doctitle when inside main header element (the fulltitle type can also be used for instance on the titlepage)
 * covertitle is not allowed in nordic dtbook; dropping it
 * added 'bridgehead' class to bridgeheads
 * added 'lic' class to lic
 * fixed table body rows not being included in the result
 * excluded table-rules-* and table-frame-* classes from table classes
 * allowed thead
 * allowed tfoot
 * allowed tbody

integration/unit testing:
 * updated sample books (dtbook, intermediate html, epub3)
 * xproc
   * added tests: dtbook-to-epub3
   * updated tests: dtbook.validate, epub3-to-dtbook, epub3-to-html.convert, epub3.validate
 * xslt
   * updated tests: dtbook-to-epub3, navdoc-to-outline, opf-to-html-metadata
   * finished the tests for all elements in epub3-to-dtbook (includes tables)

XProc step library:
 * exposed more steps in case third-party developers wants to use them easily
made regression test file DTB09317.epub valid