Downgrade Newtonsoft.Json package to 7.0.1

This is the same as on Nano.

src/Microsoft.PowerShell.Commands.Utility/project.json

@@ -61,7 +61,7 @@
             "imports": [ "dnxcore50", "portable-net45+win8" ],
             "dependencies": {
                 "Microsoft.CodeAnalysis.CSharp": "1.1.1",
-                "Newtonsoft.Json": "8.0.2",
+                "Newtonsoft.Json": "7.0.1",
                 "System.Diagnostics.TextWriterTraceListener": "4.0.0"
             }
         },

src/Microsoft.PowerShell.ConsoleHost/project.json

@@ -47,7 +47,7 @@
                 "define": [ "CORECLR", "PORTABLE" ]
             },
             "dependencies": {
-                "Newtonsoft.Json": "8.0.2",
+                "Newtonsoft.Json": "7.0.1",
                 "System.Xml.XDocument": "4.0.11",
                 "System.IO.MemoryMappedFiles": "4.0.0"
             }