am/latex

   Check whether bibtex is used at all before running it.

doc/Makefile.am
   Ignore subdirectory refinement if INKSCAPE is missing.

doc/refinement/Makefile.am
   Give a resonable error message if INKSCAPE is missing and someone
   runs make directly in doc/refinement.

[[Imported from SVN: r524]]

doc/Makefile.am

 # $Id$
 
-SUBDIRS = devel appl refinement doxygen layout istl
+if INKSCAPE
+INKSCAPE_SUBDIRS = refinement
+endif INKSCAPE
+SUBDIRS = devel appl $(INKSCAPE_SUBDIRS) doxygen layout istl
 
 if BUILD_DOCS
  PAGES = index.html buildsystem.html view-concept.html installation-notes.html