Contribs: add microdns package

contrib/src/microdns/SHA512SUMS

+8bdfb93a155514d0d284d677cc34cd4a7b2fda099f6618a014fa3a2816bb67cebf882efc5809ef023ba542ba821cb126767f9c73f96ba600d95583d71d6b5d08  libmicrodns-0.0.1.tar.gz

contrib/src/microdns/rules.mak

+# libmicrodns
+
+LIBMICRODNS_VERSION := 0.0.1
+LIBMICRODNS_URL := https://github.com/videolabs/libmicrodns/releases/download/$(LIBMICRODNS_VERSION)/microdns-$(LIBMICRODNS_VERSION).tar.gz
+
+ifeq ($(call need_pkg,"microdns >= 0.0.1"),)
+PKGS_FOUND += libmicrodns
+endif
+
+$(TARBALLS)/libmicrodns-$(LIBMICRODNS_VERSION).tar.gz:
+	$(call download,$(LIBMICRODNS_URL))
+
+.sum-microdns: $(TARBALLS)/libmicrodns-$(LIBMICRODNS_VERSION).tar.gz
+
+microdns: libmicrodns-$(LIBMICRODNS_VERSION).tar.gz .sum-microdns
+	$(UNPACK)
+	mv microdns-$(LIBMICRODNS_VERSION) microdns
+
+.microdns: microdns
+	cd $< && $(HOSTVARS) ./configure $(HOSTCONF)
+	cd $< && $(MAKE) install
+	touch $@