Separate graph generation from make tidy, add make target docs

CONTRIBUTING.md

@@ -9,3 +9,27 @@ We gratefully welcome improvements to documentation as well as to code.
 ## Guidelines
 
 TODO: Add contributing guidelines here after we formalize them.
+
+## Make targets
+
+To compile the `ignite` binary, run
+```
+make
+```
+
+To compile the `ignite-spawn` binary and build the Docker image, run
+```
+make ignite-spawn
+```
+
+Before submitting a PR, run
+```
+make tidy
+```
+
+Other targets:
+- Install the `ignite` binary: `make install`
+- (Re)generate autogenerated content: `make autogen`
+- Generate dependency graph: `make graph`
+  - Depends on `sfdp` (usually found in the `graphviz` package)
+- Push the `weaveworks/ignite` Docker image: `make image-push`

Makefile

@@ -47,9 +47,11 @@ tidy: $(API_DOCS)
 	gofmt -s -w pkg cmd
 	goimports -w pkg cmd
 	hack/generate-client.sh
-	hack/graph.sh
 	go run hack/cobra.go
 
+graph:
+	hack/graph.sh
+
 .PHONY: $(API_DOCS)
 $(API_DOCS): api/%.md: $(CACHE_DIR)/go/bin/godoc2md
 	mkdir -p $$(dirname $@) bin/tmp/$*