Re-enable multi-targeting (#605)

Fixes #600 

* Re-enable multi-targeting
* Revert changes made in 555cabf
* Fix errors for ManagementClient that was added when only netstandard2.0 was targeted.

Author: SeanFeldman

src/Microsoft.Azure.ServiceBus/Microsoft.Azure.ServiceBus.csproj

@@ -5,7 +5,7 @@
     <Version>3.1.1</Version>
     <Authors>Microsoft</Authors>
     <copyright>© Microsoft Corporation. All rights reserved.</copyright>
-    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
     <AssemblyOriginatorKeyFile>../../build/keyfile.snk</AssemblyOriginatorKeyFile>
     <SignAssembly>true</SignAssembly>
     <PublicSign Condition=" '$(OS)' != 'Windows_NT' ">true</PublicSign>
@@ -35,6 +35,12 @@
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0-beta-63127-02" PrivateAssets="All" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)' == 'net461'">
+    <Reference Include="System.Transactions" />
+    <Reference Include="System.Net.Http" />
+    <Reference Include="System.Web" />
+  </ItemGroup>
+
   <ItemGroup>
     <Compile Update="Resources.Designer.cs">
       <DesignTime>True</DesignTime>

test/Microsoft.Azure.ServiceBus.UnitTests/Microsoft.Azure.ServiceBus.UnitTests.csproj

@@ -21,6 +21,7 @@
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\OnMessageQueueTests.cs" />
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\OnSessionQueueTests.cs" />
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\RetryTests.cs" />
+    <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\TransactionTests.cs" />
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\SubscriptionClientTests.cs" />
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\Diagnostics\ExtractActivityTests.cs" />
     <compile Remove="..\..\test\Microsoft.Azure.ServiceBus.UnitTests\Diagnostics\SessionDiagnosticsTests.cs" />
@@ -57,6 +58,6 @@
   <ItemGroup Condition="'$(TargetFramework)' == 'net461'">
     <PackageReference Include="WindowsAzure.ServiceBus" Version="4.1.2" />
   </ItemGroup>
-  
+
 
 </Project>