The count of file references is different on different platform. It is
not essential to the test since there are assertion to test required
references' existence.
Update .exe's project.json Target Framework from dnxcore50 to netstandardapp1.5.
Update .dll's project.json Target Framework from dnxcore50 to netstandard1.3.
Adding workaround for DataContractSerialization to src\dotnet\project.json to fix crossgen issue.
Build 23901 has a dependency issue that doesn't allow the runtime.any.System.Private.DataContractSerialization
package to be restored. When we move to a new build of CoreFX we should take this workaround out.
1. Address the null reference exception when a project dependency is
broken.
2. Address the duplicate key issues after the logic of redirecting
System pacage to reference assembly was added
Update projectmodel-server and tests
1. Fix test timeout caused by undisconnected socket;
2. Update project model server
