websearch/bibformat: metadata in header of hd records

  * Metadata suitable for google scholar harvest exposed
    in headers of detailed record pages.  see:

http://scholar.google.com/intl/en/scholar/inclusion.html

  * websearch medified to emit meta tags in headers, and
    regression test for metadata header

  * Relies on configuration within tags table in DB, but
    uses a minimal set of defaults that are generally
    acceptable.  HDM format can be modified, or tag names
    changed.

  * invenio.conf variable introduces to control which format is
    used (default HDM)
Bibformat: appropriate output for Google Scholar

    * HTML Detailed Meta format added
    * HTML Detailed Meta should also contain a field citation_issn
      which should be populated with the issn.  It seems overly
      complicated at the moment... TODO
bibformat: remove duplicate titles in metadata
Websearch: Inclusion of Google Scholar-harvestable

    * reformatted dates to be yyyy/mm instead of yyyy-mm
BibFormat: new escaping modes (8, 9)

 * New escaping mode (8): use cgi.escape() with 'quote=True' to also
   escape double-quotes.

 * New escaping mode (9): remove all HTML tags and escape
   double-quotes.
WebSearch: add Open Graph markup

 * Enhanced bfe_meta to support knowledge bases and variables.

 * Added bfe_meta_opengraph_image.py and bfe_meta_opengraph_video.py
   to deal specifically with insertion of images and videos.

 * Added CFG_WEBSEARCH_ENABLE_GOOGLESCHOLAR and CFG_WEBSEARCH_ENABLE_OPENGRAPH
   to configure use of Google Scholar or Open Graph protocol markup
   in the page header.

 * Remove duplicate values for a given tag.

 * Added demo 'COLLECTION_TO_OPENGRAPHTYPE' knowledge base to map
   collection identifier to Open Graph object type.

 * Other small fixed and enhancements.
WebJournal: add Open Graph markup
inveniogc: clean more temporary files

* Removes temporary file preview icons websubmit_icon_creator_*
* Removes temporary file stamps websubmit_file_stamper_*
* Removes temporary WebJournal XML update files webjournal_publish_*
* Removes temporary CKEditor file attachments in CFG_PREFIX/var/tmp/attachfile/
mailutils: header/footer in scheduled_send_email()

* Passes 'header' and 'footer' params to "bst_send_email" tasklet
  called from scheduled_send_email() function.  (closes #1030)
Merge branch 'jerome/630-google-scholar-and-open-graph'

* jerome/630-google-scholar-and-open-graph:
  WebJournal: add Open Graph markup
  WebSearch: add Open Graph markup
  BibFormat: new escaping modes (8, 9)
  Websearch: Inclusion of Google Scholar-harvestable
  bibformat: remove duplicate titles in metadata
  Bibformat: appropriate output for Google Scholar
  websearch/bibformat: metadata in header of hd records

Conflicts:
	config/invenio.conf
BibFormat: enable copyright/license linkage via $3

* Copyright (542__) and license (540__) fields can be linked together
  via their $3 subfield (material).

* New parameter 'show_material' to switch on/off display of $3 subfield.

* New parameter 'license_to_url_kb' to enable linking from a license to
  its URL when the URL is not specified in the metadata.
  Adds sample knowledge base 'LICENSE2URL'.

Conflicts:

	modules/miscutil/demo/democfgdata.sql