Many improvements to the modularity and stability of the DBNL codebase.

* [DBNL,SC] dbnl_primary/3 and dbnl_secondary/3 are now wrappers around dbnl_text/4, scraping the text (if this was not done already) and relating it to a title.
* [DBNL,FIX] Assert the XPath namespace in every module where it is used.
* [DBNL_DB,NEW] Added dbnl_assert_[part,text,year]/[3,4], making it earier and more modular to assert DBNL stuff. E.g. the year assertions should be used everywhere.
* [DBNL_EXTRACT,NEW] Added dbnl_extract_year_end/3 for extracting years that occur at the end of an atom (using in DBNL_TITLE).
* [DBNL_TEXT,EXT] Added parsing of the contents of paragraphs.
* [DBNL_TEXT,EXT] Added parsing of definition lists. Currently two cases:
** The DBNL logo (skipped).
** A list of part or volumes for a title.
* [DBNL_TITLE,EXT] Added parsing of years that occur in the title (at the end of the title).
Complete a rearchitecture of the way in which titles, texts (volume collections, table of centents, and plain texts) are scraped, parsed, and asserted. We now move to testing this...

* [DBNL_BIBLIOGRAPHY,EXT] Updated this module to work with the rearchitecture.
* [DBNL_DB,NEW] Added dbnl_assert_[bibliography,toc,volume]/3.
* [DBNL_TEXT,NEW] Added dbnl_text_content/3 for adding XML contents to a text resource.
* [DBNL_TEXT,EXT] dbnl_text/4 recognizes whether a text is a table of contents or a volume collection.
* [DBNL_TOC,SC] Vastly simplified this module.
* [DBNL_TEXT,EXT] Now pick up on text that already contains contents (DBNL markup).
* [DBNL_TEXT,EXT] Support for non-empty subtitles.
* [DBNL_TEXT,EXT] Support for PDF file media links and single-space atomic contents (both are skipped).
* [XPATH_EXT,NEW] Very simple extension of library/xpath.
Various extensions and additions. Parsing success is now incremental. Architecture seems sound.

* [DBNL_EXTRACT,EXT] Find editors that are chief editors.
* [DBNL_GENERIC,SC] Added generic methods for finding copyright and DBNL logo (modularity, reuse).
* [DBNL_GENERIC,FIX] Changes to the DOM predicates that find all TEXT, LEFT and RIGHT parts.
* [DBNL_MARKUP,EXT] Added support for letter-spaced text.
* [DBNL_MARKUP,EXT] Do not include paragraphs that evaluate to no content.
* [DBNL_TEXT,EXT] Started parsing the left DIV for text pages (see module DBNL_TEXT_LEFT).
* [DBNL_TEXT,EXT] Assert the author and editor temporarily in order to disambiguated in left DIV (where the URI is fetched).
* [DBNL_TEXT,EXT] Support parsing inside DIV content.
* [DBNL_TEXT_LEFT,NEW] Separate module for parsing the left DIV of a DBNL text page.
* [DBNL_TOC,FIX] Some paragraphs have two link elements to chapter contents.
Various extensions, mostly to the left DIV of text pages.

* [DBNL_DB,NEW] Added dbnl_assert_journal/4.
* [DBNL_DB,EXT] Allow authors whose name start with '[tijdschrift]' to be asserted as a journal.
* [DBNL_TEXT,EXT] Support for empty headers and interp element (both skipped).
* [DBNL_TEXT_LEFT,EXT] Skip superfluous headers and line breaks.
* [DBNL_TEXT_LEFT,EXT] Parse the contents of paragraphs and DIVs.
* [DBNL_TEXT_LEFT,EXT] Support for justification texts.
* [DBNL_TEXT_LEFT,EXT] Better parsing of journal name, journal year, publisher, publisher place, publisher year.
Various extensions, allowing more pages to be scraped.

* [DBNL_DOWNLOADS,SC] Rewrote this module to fit the new architecture (modular, extensible).
* [DBNL_GENERIC,NEW] Added dbnl_uri_resolve/3 which gives alterinatives in case dbnl_uri_resolve/2 does not work.
* [DBNL_MARKUP,NEW] Added dbnl_markup_simple/2 for atomic (i.e., non-XML) markup.
* [DBNL_MARKUP,EXT] Added support for two kinds of *-sectation indicators.
* [DBNL_TEXT,EXT] Also parse download pages (see module DBNL_DOWNLOADS).
* [DBNL_TEXT,EXT] Extended h1-titles, can now parse atomic markup.
* [DBNL_TEXT_LEFT,EXT] Add the chosen class option for various pages (not scraped if chosen).
* [DBNL_MARKUP,EXT] Added support for small caps.
* [DBNL_TEXT,EXT] Started the parsing of the right DIV.