re-enable target frameworks

Author: antonfirsov

src/ImageSharp.Drawing/ImageSharp.Drawing.csproj

@@ -11,8 +11,7 @@
     <VersionPrefix Condition="$(packageversion) != ''">$(packageversion)</VersionPrefix>
     <VersionPrefix Condition="$(packageversion) == ''">0.0.1</VersionPrefix>
 
-    <!--<TargetFrameworks>netcoreapp2.1;netstandard1.3;netstandard2.0</TargetFrameworks>-->
-    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFrameworks>netcoreapp2.1;netstandard1.3;netstandard2.0</TargetFrameworks>
 
     <LangVersion>7.3</LangVersion>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>

tests/ImageSharp.Tests/ImageSharp.Tests.csproj

@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <!--<TargetFrameworks>netcoreapp2.1;net462;net472</TargetFrameworks>-->
-    <TargetFramework>netcoreapp2.1</TargetFramework>
+    <TargetFrameworks>netcoreapp2.1;net462;net472</TargetFrameworks>
     <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
     <LangVersion>latest</LangVersion>
     <DebugType Condition="$(codecov) != ''">full</DebugType>