Add support casting System.Drawing.Color to Discord.Color

src/Discord.Net.Core/Discord.Net.Core.csproj

@@ -4,8 +4,9 @@
     <AssemblyName>Discord.Net.Core</AssemblyName>
     <RootNamespace>Discord</RootNamespace>
     <Description>The core components for the Discord.Net library.</Description>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">net45;netstandard1.1;netstandard1.3</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' != 'Windows_NT' ">netstandard1.1;netstandard1.3</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">net45;netstandard1.1;netstandard1.3;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' != 'Windows_NT' ">netstandard1.1;netstandard1.3;netstandard2.0</TargetFrameworks>
+    <DefineConstants Condition=" '$(TargetFramework)' == 'netstandard2.0' ">NETSTANDARD2</DefineConstants>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="10.0.2" />

src/Discord.Net.Core/Entities/Roles/Color.cs

@@ -1,5 +1,8 @@
 using System;
 using System.Diagnostics;
+#if NETSTANDARD2
+using StandardColor = System.Drawing.Color;
+#endif
 
 namespace Discord
 {
@@ -96,7 +99,14 @@ namespace Discord
                 ((uint)(g * 255.0f) << 8) |
                 (uint)(b * 255.0f);
         }
-        
+
+#if NETSTANDARD2
+        public static implicit operator StandardColor(Color color) =>
+            StandardColor.FromArgb((int)color.RawValue);
+        public static explicit operator Color(StandardColor color) =>
+            new Color((uint)color.ToArgb() << 8 >> 8);
+#endif
+
         public override string ToString() =>
             $"#{Convert.ToString(RawValue, 16)}";
         private string DebuggerDisplay =>