customize first id

public/locales/en.json

@@ -76,6 +76,7 @@
   "tree.name": "Tree name",
   "tree.desc": "Tree desc",
   "tree.export": "Export",
+  "tree.firstid": "First id",
 
   "regnode.input": "Input: ",
   "regnode.output": "Output: ",

public/locales/zh.json

@@ -76,6 +76,7 @@
   "tree.name": "行为树",
   "tree.desc": "说明",
   "tree.export": "导出",
+  "tree.firstid": "起始标识",
 
   "regnode.input": "输入：",
   "regnode.output": "输出：",