dev: initial environment

fedora, centos and ubuntu

* fewer layers
* systemd-dev
* basic pieces for building docker everytime
* centos updates
* better automated build

centos-dev/Makefile

@@ -0,0 +1,26 @@
+
+DOCKER		?= $(shell which docker)
+FROM_IMAGE	?= centos
+FROM_TAG	?= latest
+FROM		:= $(FROM_IMAGE):$(FROM_TAG)
+REGISTRY	?= docker.usersys
+NAME		?= $(REGISTRY)/$(USER)/$(FROM_IMAGE)-dev:$(FROM_TAG)
+
+default: build
+
+Dockerfile: Dockerfile.in
+	m4 --define=DEV_USER=$(USER) --define=FROM_IMAGE=$(FROM) $< > $@
+
+build: .build
+
+.build: Dockerfile .pull
+	$(DOCKER) build -t $(NAME) . && touch $@
+
+pull: .pull
+
+.pull: 
+	$(DOCKER) pull $(FROM) && touch $@
+
+clean:
+	rm -rf .build .pull Dockerfile *~
+