The caption inset patch by Georg, Martin and myself.

The caption inset patch by Georg, Martin and myself.

* buffer.C: increase LyX format to 257.

* lyxtextclass.C: increase FORMAT format to 3.

* buffer_funcs.C:
  - setCaptionLabels(): new recursive function
  - setCaptions(): new function
  - updateLabels(): call setCaptions() for each paragraph.

* InsetCaption:
  - add a virtual destructor
  - overload InsetText' getStatus() and wide().
  - setLabel(): only set the new private member label_.
  - metrics(): don't set label here and correct for title metrics.
  - draw(): don't set label here
  - latex(): fix optional argument.
  - plaintext(): implement!

* InsetText:
  - add a virtual destructor
  - add virtual to getStatus() and wide().

*  output_latex.[Ch]: move latexOptArgInsets() out of anon namespace.

* text3.C: enable LFUN_CAPTION_INSERT

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@16948 a592a061-630c-0410-9148-cb99ea01b6c8