Fix build

- Hoist packages using netstandard.library
- Upgrade process since it's not in the standard library

Author: davidfowl

test/Microsoft.AspNetCore.Hosting.Tests/project.json

@@ -12,13 +12,14 @@
     "Microsoft.AspNetCore.Testing": "1.0.0-*",
     "Microsoft.Extensions.Options": "1.0.0-*",
     "Microsoft.Extensions.PlatformAbstractions": "1.0.0-*",
-    "Microsoft.NETCore.Platforms": "1.0.1-*",
     "xunit": "2.1.0"
   },
   "frameworks": {
     "netstandardapp1.5": {
       "dependencies": {
-        "dotnet-test-xunit": "1.0.0-dev-*"
+        "dotnet-test-xunit": "1.0.0-dev-*",
+        "NETStandard.Library": "1.5.0-*",
+        "System.Diagnostics.Process": "4.1.0-*"
       },
       "imports": [
         "dnxcore50",

test/Microsoft.AspNetCore.TestHost.Tests/project.json

@@ -7,13 +7,14 @@
     "Microsoft.AspNetCore.TestHost": "1.0.0-*",
     "Microsoft.AspNetCore.Testing": "1.0.0-*",
     "Microsoft.Extensions.DiagnosticAdapter": "1.0.0-*",
-    "Microsoft.NETCore.Platforms": "1.0.1-*",
     "xunit": "2.1.0"
   },
   "frameworks": {
     "netstandardapp1.5": {
       "dependencies": {
-        "dotnet-test-xunit": "1.0.0-dev-*"
+        "dotnet-test-xunit": "1.0.0-dev-*",
+        "NETStandard.Library": "1.5.0-*",
+        "System.Diagnostics.Process": "4.1.0-*"
       },
       "imports": [
         "dnxcore50",