Link to migration instruction

Author: piroor

webextensions/_locales/en/messages.json

@@ -165,6 +165,10 @@
   "migration.configsFailed.notification.message": { "message": "Migration process is aborted due to unexpected problem." },
 
   "config.importedTreeStructureFromLegacy.label": { "message": "Migration of Old Tree" },
+  "config.migrateSessionStore.before":     { "message": "See" },
+  "config.migrateSessionStore.link.label": { "message": "the instruction for manual migration of tree information" },
+  "config.migrateSessionStore.link.uri":   { "message": "https://github.com/piroor/treestyletab/wiki/How-to-convert-session-information-from-old-TST-0.19.x-to-new-TST-2.x" },
+  "config.migrateSessionStore.after":      { "message": "also." },
   "config.migrateLegacyTreeStructure.label": { "message": "Migrate tree of tabs at the next startup" },
   "config.importedTreeStructureFromLegacy.placeholder": { "message": "Paste migration data for old tree here" },
   "migration.tree.notification.title": { "message": "Tree Style Tab: Tree of tabs are successfully migrated" },

webextensions/_locales/ja/messages.json

@@ -164,6 +164,10 @@
   "migration.configsFailed.notification.message": { "message": "設定の移行中に想定外の問題が発生したため、移行処理を中断しました。" },
 
   "config.importedTreeStructureFromLegacy.label": { "message": "旧バージョンからのツリー情報の移行" },
+  "config.migrateSessionStore.before":     { "message": "" },
+  "config.migrateSessionStore.link.label": { "message": "ツリー情報の手動での移行手順" },
+  "config.migrateSessionStore.link.uri":   { "message": "https://github.com/piroor/treestyletab/wiki/How-to-convert-session-information-from-old-TST-0.19.x-to-new-TST-2.x" },
+  "config.migrateSessionStore.after":      { "message": "も参照して下さい。" },
   "config.migrateLegacyTreeStructure.label": { "message": "次回初期化時にツリー情報を復元する" },
   "config.importedTreeStructureFromLegacy.placeholder": { "message": "旧バージョンからのツリー情報移行用データをここに貼り付けてください" },
   "migration.tree.notification.title": { "message": "ツリー型タブ：ツリー情報の移行に成功しました" },

webextensions/options/options.html

@@ -255,6 +255,9 @@ <h1>__MSG_config.advanced.caption__</h1>
     </fieldset>
     <fieldset>
       <legend>__MSG_config.importedTreeStructureFromLegacy.label__</legend>
+      <p>__MSG_config.migrateSessionStore.before__
+         <a href="__MSG_config.migrateSessionStore.link.uri__">__MSG_config.migrateSessionStore.link.label__</a>
+         __MSG_config.migrateSessionStore.after__</p>
       <p><label><input id="migrateLegacyTreeStructure"
                        type="checkbox">
                __MSG_config.migrateLegacyTreeStructure.label__</label></p>