Update SS.Interfaces dll

Author: mythz

lib/ServiceStack.Interfaces.dll

@@ -71,6 +71,7 @@
     <PlatformTarget>AnyCPU</PlatformTarget>
     <ErrorReport>prompt</ErrorReport>
     <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+    <WarningLevel>4</WarningLevel>
   </PropertyGroup>
   <PropertyGroup>
     <SignAssembly>true</SignAssembly>
@@ -82,16 +83,10 @@
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="System" />
     <Reference Include="System.Configuration" />
-    <Reference Include="System.Core">
-      <RequiredTargetFramework>3.5</RequiredTargetFramework>
-    </Reference>
+    <Reference Include="System.Core" />
     <Reference Include="System.Data.Linq" />
-    <Reference Include="System.Runtime.Serialization">
-      <RequiredTargetFramework>3.0</RequiredTargetFramework>
-    </Reference>
-    <Reference Include="System.Xml.Linq">
-      <RequiredTargetFramework>3.5</RequiredTargetFramework>
-    </Reference>
+    <Reference Include="System.Runtime.Serialization" />
+    <Reference Include="System.Xml.Linq" />
     <Reference Include="System.Data" />
     <Reference Include="System.Xml" />
   </ItemGroup>