Fixup docs clean target

ghisvail · web-flow · commit 9c80e98d8825 · 2017-04-06T14:03:26.000+01:00
Same fix as for `xtensor`
diff --git a/docs/Makefile b/docs/Makefile
@@ -49,6 +49,7 @@ help:
 
 clean:
 	rm -rf $(BUILDDIR)/*
+	rm -rf xml
 
 html:
 	doxygen
