(GH-775) Add ability to skip duplicate package version during push

This allows duplicate NuGet packages to not throw
any errors when there is a duplicate package version
in the upstream repository, and instead allow the
build to continue without any failures

Cake.Recipe/Content/packages.cake

@@ -261,7 +261,8 @@ public void PushNuGetPackages(ICakeContext context, bool isRelease, List<Package
 
  var nugetPushSettings = new NuGetPushSettings
  {
- Source = nugetSource.PushUrl
+ Source = nugetSource.PushUrl,
+ SkipDuplicate = ToolSettings.SkipDuplicatePackages
  };
 
  var canPushToNuGetSource = false;

Cake.Recipe/Content/toolsettings.cake

@@ -16,6 +16,7 @@ public static class ToolSettings
  public static MSBuildToolVersion BuildMSBuildToolVersion { get; private set; }
  public static int MaxCpuCount { get; private set; }
  public static string TargetFrameworkPathOverride { get; private set; }
+ public static bool SkipDuplicatePackages { get; private set; }
 
  public static string CodecovTool { get; private set; }
  public static string CoverallsTool { get; private set; }
@@ -99,7 +100,8 @@ public static class ToolSettings
  DirectoryPath targetFrameworkPathOverride = null,
  string[] dupFinderExcludeFilesByStartingCommentSubstring = null,
  int? dupFinderDiscardCost = null,
- bool? dupFinderThrowExceptionOnFindingDuplicates = null
+ bool? dupFinderThrowExceptionOnFindingDuplicates = null,
+ bool skipDuplicatePackages = false
  )
  {
  context.Information("Setting up tools...");

docs/input/docs/fundamentals/set-tool-settings.md

@@ -161,3 +161,11 @@ This is used when executing the DupFinder command line tool. If set to true, an
 Type: `bool?`
 
 Default Value: `null`
+
+### skipDuplicatesPackages
+
+This is used to tell NuGet to ignore issues with trying to push package versions when the version already exist upstream, instead of failing the build.
+
+Type: `bool`
+
+Default Value: `false`