add help entry for init

cmd/main.go

@@ -359,6 +359,9 @@ func main() {
 				fmt.Println("  generate  Generate a repository from a directory containing EPKs.")
 			case "package":
 				fmt.Println("Usage: eternity package <epk>")
+			case "init":
+				fmt.Println("Usage: eternity init [directory]")
+				fmt.Println("  directory    Create a new directory with the given name and an eternity.json file. Defaults to the current directory.")
 			default:
 				fmt.Println("Usage: eternity help <build/generate/convert/repo/package>")
 			}