remove use of -- seems to be unnecessary and causing other problems

doc/Makefile

@@ -20,7 +20,6 @@ ALLSPHINXOPTS   = $(SPHINX_OUTPUT) $(SPHINXOPTS) .
 html:  gallery
 	cp sphinx/ext_mathjax.py extensions.py
 	$(SPHINXBUILD) -b html $(SPHINX_OUTPUT) $(SPHINX_OPTS) . $(BUILDDIR)/html
-	./filter_spurious_link_from_html.py
 	@echo
 	@echo "html build finished: $(BUILDDIR)/html."
 
@@ -38,7 +37,6 @@ examples/index.rst:
 htmlzip: html
 	cp sphinx/ext_mathjax.py extensions.py
 	$(SPHINXBUILD) -b html $(SPHINX_OUTPUT) $(SPHINX_OPTS) . $(BUILDDIR)/lmfit_doc
-	./filter_spurious_link_from_html.py
 	cd $(BUILDDIR) && zip -pur html/lmfit_doc.zip lmfit_doc
 
 epub: gallery