Add makefile and example

Makefile

@@ -0,0 +1,29 @@
+.PHONY: all clean
+.SUFFIXES: .dot .pdf .svg .tex
+
+DB = db.sqlite3
+DOT = dot
+DOTTOTEX = dot2tex
+MANAGE = ./manage.py
+TAGDAG = $(MANAGE) tagdag --threshold 1
+
+all: graphs/citations.svg graphs/sok.svg
+
+clean:
+	rm -f graphs/*.dot
+	rm -f graphs/*.svg
+
+.dot.pdf:
+	$(DOT) -Tpdf -o$*.pdf $<
+
+.dot.svg:
+	$(DOT) -Tsvg -o$*.svg $<
+
+.dot.tex:
+	$(DOTTOTEX) -f tikz --usepdflatex $< > $@
+
+graphs/citations.dot: $(DB) sok/management/commands/citations.py
+	$(MANAGE) citations --pk --min-citations 10 > $@
+
+graphs/sok.dot: $(DB) sok/management/commands/tagdag.py
+	$(TAGDAG) > $@