Add new nuget config file.

nuget.config

+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+    <packageSources>
+        <clear />
+        <add key="nuget" value="https://nuget.aiursoft.cn/v3/index.json" />
+    </packageSources>
+</configuration>
\ No newline at end of file