Use echo -e for generating version.go

Flag -e is to "enable interpretation of backslash escapes"
Which might be a default, depends on a shell.

sh -c 'echo "a\nb"' on my OS prints "a\nb" (no newline)

desktop/Makefile

@@ -26,8 +26,8 @@ $(GOBIN)/rice:
 # Embed the current version numbers in the executable by writing version.go
 .PHONY: version.go
 version.go:
-	@echo "// DO NOT EDIT: Autogenerated by Makefile\n" > version.go
-	@echo "package main\n" >> version.go
+	@echo -e "// DO NOT EDIT: Autogenerated by Makefile\n" > version.go
+	@echo -e " package main\n" >> version.go
 	@echo "const DesktopVersion = \"$(DESKTOP_VERSION)\"" >> version.go
 	@echo "const EditorVersion = \"$(EDITOR_VERSION)\"" >> version.go