feat: 后端全量更新 - 含所有本次需求

- Contract.php: 返回合约账户余额(balance_contract)
- My.php: 地址管理增加BTC/ETH
- AppContract.php: 一键平仓(closeall)
- AppProxy.php: 代理专属注册链接 + 分级权限(L1/L2)
- site.php: 手续费减半(0.018→0.009)
- agent_permission_setup.sql: 代理权限SQL
- crypto_news_crawler.py: 新闻自动采集脚本

public/assets/libs/eonasdan-bootstrap-datetimepicker/README.md

@@ -0,0 +1,20 @@
+# Bootstrap 3 Date/Time Picker
+![GitHub version](https://badge.fury.io/gh/Eonasdan%2Fbootstrap-datetimepicker.png)   ![Travis](https://travis-ci.org/Eonasdan/bootstrap-datetimepicker.svg?branch=development)
+
+![DateTimePicker](http://i.imgur.com/nfnvh5g.png)
+
+## [View the manual and demos](http://eonasdan.github.io/bootstrap-datetimepicker/)
+
+## [Installation instructions](http://eonasdan.github.io/bootstrap-datetimepicker/Installing/)
+
+## [Change Log](http://eonasdan.github.io/bootstrap-datetimepicker/Changelog/)
+
+### This issue tracker is no longer actively monitored.
+
+# Version 5
+
+Version 5 is being completely rewritten in ES6 and modularized as Tempus Dominus.
+
+v5 is [in alpha](https://github.com/tempusdominus/bootstrap-3).
+
+