Update NETStandard.Library implicit package reference version to 1.6.1

[dsplaisted]

• Update implicit package reference to NETStandard.Library to use version 1.6.1
• Update publish tests to expect additional files that are now published (Fixes Referencing NETStandard.Library package version 1.6.1 results in extra files published #571, after investigation it looks like it is correct that these extra files are getting included)
• Don't implicitly reference System.Net.Http or System.IO.Compression, in order to reduce impact of ResolveAssemblyReference task generating warning instead of unifying and including assembly in SuggestedRedirects ouput parameter msbuild#1329
• Add fixed version of ImplicitlyExpandDesignTimeFacades (from @cdmihai's code here) to workaround ImplicitlyExpandDesignTimeFacades target should only add facades if a higher version isn't already referenced msbuild#1345

[gulbanana]

note that this will lead to using the version of System.Net.Http from NETStandard.Library, which will trigger https://github.com/dotnet/corefx/issues/11100

[qmfrederik]

@dsplaisted I built this PR locally and tried to build my project which references NETStandard.Library for net462, but I still get this issue when building locally:

13:32:20.821   4:2>ResolveAssemblyReferences: (TargetId:35)
                         Required by "C:\Users\Frederik Carlier\Source\Repos\Quamotion\src\Nttr.RTK.Thrift\bin\Debug\net462\Nttr.RTK.Thrift.dll". (TaskId:15)
                         Required by "C:\Users\Frederik Carlier\.nuget\packages\thrift\0.9.1.3\lib\net35\Thrift.dll". (TaskId:15)
                         This reference is not "CopyLocal" because at least one source item had "Private" set to "false" and no source items had "Private" set to "true". (TaskId:15)
                         The ImageRuntimeVersion for this reference is "v4.0.30319". (TaskId:15)
                     There was a conflict between "System.Runtime, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" and "System.Runtime, Version=4.0.20.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a". (TaskId:15)
13:32:21.133   4:2>C:\Program Files\dotnet\sdk\1.0.0-preview5-004275\Microsoft.Common.CurrentVersion.targets(1909,5): warning MSB3243: No way to resolve conflict between "System.Runtime, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" and "System.Runtime, Version=4.0.20.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a". Choosing "System.Runtime, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" arbitrarily. [C:\Users\Frederik Carlier\Source\Repos\Quamotion\src\Quamotion.Devices\Quamotion.Devices.Core.csproj]

I'm using version 1.0.0-preview5-004275 of the CLI, built this patch using build.cmd and copied the content of the bin\Debug\Packages\Microsoft.NET.Sdk.1.0.0-alpha-00000001-01.nupkg file to C:\Program Files\dotnet\sdk\1.0.0-preview5-004275\Sdks\Microsoft.NET.Sdk

Not sure if just copying the output of a SDK build to the CLI folder is supposed to work, but thought I'd let you know. (I did notice the side-effects of the implicit includes so at least some of the changes to the SDK propagated correctly to my local build environment)

[qmfrederik]

@dsplaisted Ah, just noticed that these are warnings, not errors, and the build did in fact succeed. Great! So dotnet �publish now works! Looking forward to a daily cli build with this change, would be extremely helpful!

(Take the three exclamation marks as an expression of my relief that this is now working ;-))

[srivatsn]

Do we intend to add these back? can you file an issue for that?

[dsplaisted]

Filed #594

[srivatsn]

Again please file a bug on this.

[dsplaisted]

I've filed #595 for this