Allow overriding authoring package TF/restore behavior from nugetizer

Even if we do need to provide these properties in the unfolded .nuproj
anyway so that Restore works on CI, we can still provide better values
over time after the initial restore.

See also NuGet/Home#5254 for a better way in
the future to handle this.

Author: kzu

src/Build/NuGet.Build.Packaging.Tasks/NuGet.Build.Packaging.Authoring.props

@@ -11,11 +11,9 @@ Copyright (c) .NET Foundation. All rights reserved.
 -->
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
 	<PropertyGroup>
-		<!--<RestoreProjectStyle>PackageReference</RestoreProjectStyle>
+		<RestoreProjectStyle>PackageReference</RestoreProjectStyle>
 		<TargetFramework>netstandard1.0</TargetFramework>
-		<TargetFrameworkMoniker>.NETStandard,Version=1.0</TargetFrameworkMoniker>
-		<NuGetTargetMoniker>$(TargetFrameworkMoniker)</NuGetTargetMoniker>
-		<PackageTargetFallback>net11;net20;net35;net40;net403;net45;net451;net452;net46;net461;net462;netcore;netcore45;netcore451;netcore50;win8;win81;win10;sl4;sl5;wp;wp7;wp75;wp8;wp81;wpa81;uap;uap10;netstandard1.0;netstandard1.1;netstandard1.2;netstandard1.3;netstandard1.4;netstandard1.5;netstandard1.6;netstandard2.0;netcoreapp1.0;netcoreapp2.0;monoandroid;monotouch;monomac;xamarinios;xamarinmac;xamarinpsthree;xamarinpsfour;xamarinpsvita;xamarinwatchos;xamarintvos;xamarinxboxthreesixty;xamarinxboxone</PackageTargetFallback>-->
+		<PackageTargetFallback>net11;net20;net35;net40;net403;net45;net451;net452;net46;net461;net462;netcore;netcore45;netcore451;netcore50;win8;win81;win10;sl4;sl5;wp;wp7;wp75;wp8;wp81;wpa81;uap;uap10;netstandard1.0;netstandard1.1;netstandard1.2;netstandard1.3;netstandard1.4;netstandard1.5;netstandard1.6;netstandard2.0;netcoreapp1.0;netcoreapp2.0;monoandroid;monotouch;monomac;xamarinios;xamarinmac;xamarinpsthree;xamarinpsfour;xamarinpsvita;xamarinwatchos;xamarintvos;xamarinxboxthreesixty;xamarinxboxone</PackageTargetFallback>
 
 		<TargetExt>.nupkg</TargetExt>