switch to tdemin/gmnhg' md2gmn to fix gemini publishing

Makefile

@@ -8,16 +8,16 @@ target_files := $(patsubst content/%.md,gemini/%.gmi,$(source_files))
 default: build-gemini publish-gemini build-html publish-html
 
 gemini/%.gmi: content/%.md
-	lowdown -tgemini $< > $@
+	cat $< | md2gmn > $@
 
 gemini/index.gmi: $(source_files)
+	cp gemini/_index.gmi_ gemini/index.gmi
 	for file in $(target_files) ; do \
 		echo "=> $$file" | sed 's/gemini//' >> gemini/index.gmi ; \
 	done
 
 .PHONY: build-gemini
 build-gemini: $(target_files) gemini/index.gmi
-	cp gemini/_index.gmi gemini/index.gmi
 	
 .PHONY: build-html
 build-html: