chore: Add nuget package badge

Author: s2quake

README.md

@@ -1,5 +1,8 @@
 # Randora
 
+![NuGet](https://img.shields.io/nuget/v/JSSoft.Randora.svg?label=release)
+![NuGet (prerelease)](https://img.shields.io/nuget/vpre/JSSoft.Randora.svg?label=preview)
+
 A lightweight random-value utility. It provides simple APIs to generate a wide range of data: primitives, collections, enums, text, time values, shuffles, and more.
 
 ## Supported frameworks
@@ -28,7 +31,7 @@ To use it project-wide, add a using alias via GlobalUsings or your project file
 
 ```xml
 <ItemGroup>
-	<Using Include="JSSoft.Randora.RandomUtility" Alias="R" />
+  <Using Include="JSSoft.Randora.RandomUtility" Alias="R" />
 </ItemGroup>
 ```