Added custom Credentials classes with binding support to choose crede…

…ntial type. Added tests

Packages.props

@@ -0,0 +1,3 @@
+<Project>
+    <Import Project="$(RepoEngPath)/Packages.Data.props" />
+</Project>

sdk/extensions/wcf/Directory.Build.props

@@ -0,0 +1,9 @@
+<Project>
+	<!-- Need to set IsClientLibrary for CentralPackageManagement versions file in $(root)\eng\Packages.Data.props -->
+	<PropertyGroup>
+		<IsClientLibrary Condition="'$(IsClientLibrary)' == '' and $(MSBuildProjectName.StartsWith('Microsoft.'))">true</IsClientLibrary>
+		<IsTestProject Condition="'$(IsTestProject)' == '' and $(MSBuildProjectName.EndsWith('.Tests'))">true</IsTestProject>
+	</PropertyGroup>
+
+	<Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.props, $(MSBuildThisFileDirectory)..))"/>
+</Project>

sdk/extensions/wcf/Directory.Build.targets

@@ -0,0 +1,3 @@
+<Project>
+    <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.targets, $(MSBuildThisFileDirectory)..))"/>
+</Project>