Lets auto numbering of footnotes kick in from commands alone. (issue4837047)

[mtsolo]

Reviewers: ,

Message:
From Reinhold's suggestion.

Cheers,
MS

Description:
Lets auto numbering of footnotes kick in from commands alone.

Gets rid of footnote-auto-numbering in the paper block.
For now, numbers that are not used are skiped.

Please review this at http://codereview.appspot.com/4837047/

Affected files:
  M input/regression/footnote-auto-numbering-page-reset.ly
  M input/regression/footnote-auto-numbering.ly
  M input/regression/footnote-break-visibility.ly
  M input/regression/footnote-footer-padding.ly
  M input/regression/footnote-spanner.ly
  M input/regression/footnote.ly
  M lily/constrained-breaking.cc
  M lily/page-breaking.cc
  M lily/page-layout-problem.cc
  M ly/music-functions-init.ly
  M ly/paper-defaults-init.ly
  M scm/define-grob-interfaces.scm
  M scm/define-grob-properties.scm
  M scm/define-grobs.scm
  M scm/define-markup-commands.scm
  M scm/define-music-properties.scm