fix: (issues/9) Worker does not support port assignment for routers (#11)

Quite a refactor and some code cleanup.

Co-authored-by: James Wells <jwells@dragonheim.net>
Reviewed-on: #11
Co-authored-by: James Wells <jwells@noreply.localhost>
Co-committed-by: James Wells <jwells@noreply.localhost>

src/picol/README.md

@@ -0,0 +1,27 @@
+# picol.go
+
+Original http://oldblog.antirez.com/post/picol.html
+
+Sample use:
+```golang
+func CommandPuts(i *picol.Interp, argv []string, pd interface{}) (string, error) {
+	if len(argv) != 2 {
+		return "", fmt.Errorf("Wrong number of args for %s %s", argv[0], argv)
+	}
+	fmt.Println(argv[1])
+	return "", nil
+}
+...
+	interp := picol.InitInterp()
+	// add core functions
+	interp.RegisterCoreCommands()
+	// add user function
+	interp.RegisterCommand("puts", CommandPuts, nil)
+	// eval
+	result, err := interp.Eval(string(buf))
+	if err != nil {
+		fmt.Println("ERROR", err, result)
+	} else {
+		fmt.Println(result)
+	}
+```