Add qthelp docs creation.

docs/Makefile

@@ -6,6 +6,7 b' SPHINXOPTS ='
 SPHINXBUILD   = sphinx-build
 PAPER         =
 SRCDIR        = source
+BUILDDIR      = build
 
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
@@ -78,6 +79,16 b' htmlhelp:'
 	@echo "Build finished; now you can run HTML Help Workshop with the" \
 	      ".hhp project file in build/htmlhelp."
 
+qthelp:
+	mkdir -p build/qthelp
+	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) build/qthelp
+	@echo
+	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
+	      ".qhcp project file in $(BUILDDIR)/qthelp, like this:"
+	@echo "# qcollectiongenerator $(BUILDDIR)/qthelp/IPython.qhcp"
+	@echo "To view the help file:"
+	@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/IPython.qhc"
+
 latex: api
 	mkdir -p build/latex build/doctrees
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) build/latex