Small clean ups (#5)

* Fix two small compiler errors

Apparently, in go, `fmt.Prntln("\n")` is a build error - you can't
have a redundant newline there. Also, we had the wrong format string
somewhere.

* Use $GOPATH to find dep

When I first pulled this branch, all the tests failed because,
although `dep` was being installed to my local machine, it wasn't
being added to $PATH. Rather than mess with $PATH, I decided to
add $GOPATH/bin to the beginning of the invocation.

Makefile

@@ -13,7 +13,7 @@ install: deps
 
 deps:
 	command -v dep >/dev/null || go get -u github.com/golang/dep/cmd/dep
-	dep ensure
+	$(GOPATH)/bin/dep ensure
 
 test: build
 	@! git grep tcell -- ':!tui/' ':!Gopkg.lock' ':!Gopkg.toml' ':!Makefile'

filetree/node_test.go

@@ -43,7 +43,7 @@ func TestAddChild(t *testing.T) {
 	}
 
 	if *two.Data != *new(FileChangeInfo) {
-		t.Errorf("Expected 'twos' payload to be nil got %d.", two.Data)
+		t.Errorf("Expected 'twos' payload to be nil got %+v.", two.Data)
 	}
 
 }

image/image.go

@@ -92,7 +92,7 @@ func WriteImage() {
 
 		fmt.Printf("Image: %s\nId: %s\nParent: %s\nLayers: %d\n%sHistory: %s\n", imageID, inspect.ID, inspect.Parent, len(inspect.RootFS.Layers), layerStr, historyStr)
 
-		fmt.Println("\n")
+		fmt.Println("")
 
 		if inspect.Parent == "" {
 			break