(chocolatey#2200) upgrade exit 2 if nothing to do

If enhanced exit codes are enabled, this sets the upgrade command to
exit with 2 if there is nothing to do (i.e. if no packages are
upgraded).

This entails returning the number of successful package results from
the report_action_summary. This is returned as a Tuple, which is not
ideal as it's members are not named, but this should be able to be
switched to named members after this is uplifted to .Net 4.7 or higher.

src/chocolatey/infrastructure.app/commands/ChocolateyUpgradeCommand.cs

@@ -339,6 +339,7 @@ Exit codes that normally result from running this command.
 Normal:
  - 0: operation was successful, no issues detected
  - -1 or 1: an error has occurred
+ - 2: nothing to do, no packages outdated
 
 Package Exit Codes:
  - 1641: success, reboot initiated

src/chocolatey/infrastructure.app/services/ChocolateyPackageService.cs

@@ -617,8 +617,8 @@ public virtual ConcurrentDictionary<string, PackageResult> install_run(Chocolate
             }
             finally
             {
-                var installFailures = report_action_summary(packageInstalls, "installed");
-                if (installFailures != 0 && Environment.ExitCode == 0)
+                var actionSummaryResults = report_action_summary(packageInstalls, "installed");
+                if (actionSummaryResults.Item2 != 0 && Environment.ExitCode == 0)
                 {
                     Environment.ExitCode = 1;
                 }
@@ -812,7 +812,7 @@ public void upgrade_noop(ChocolateyConfiguration config)
             var noopUpgrades = perform_source_runner_function(config, r => r.upgrade_noop(config, action));
             if (config.RegularOutput)
             {
-                var noopFailures = report_action_summary(noopUpgrades, "can upgrade");
+                var actionSummaryResult = report_action_summary(noopUpgrades, "can upgrade");
             }
 
             randomly_notify_about_pro_business(config);
@@ -865,12 +865,17 @@ public virtual ConcurrentDictionary<string, PackageResult> upgrade_run(Chocolate
             }
             finally
             {
-                var upgradeFailures = report_action_summary(packageUpgrades, "upgraded");
-                if (upgradeFailures != 0 && Environment.ExitCode == 0)
+                var actionSummaryResult = report_action_summary(packageUpgrades, "upgraded");
+                if (actionSummaryResult.Item2 != 0 && Environment.ExitCode == 0)
                 {
                     Environment.ExitCode = 1;
                 }
 
+                if ((actionSummaryResult.Item1 + actionSummaryResult.Item2 == 0) && Environment.ExitCode == 0)
+                {
+                    Environment.ExitCode = 2;
+                }
+
                 randomly_notify_about_pro_business(config);
             }
 
@@ -941,13 +946,13 @@ public virtual ConcurrentDictionary<string, PackageResult> uninstall_run(Chocola
             }
             finally
             {
-                var uninstallFailures = report_action_summary(packageUninstalls, "uninstalled");
-                if (uninstallFailures != 0 && Environment.ExitCode == 0)
+                var actionSummaryResult = report_action_summary(packageUninstalls, "uninstalled");
+                if (actionSummaryResult.Item2 != 0 && Environment.ExitCode == 0)
                 {
                     Environment.ExitCode = 1;
                 }
 
-                if (uninstallFailures != 0)
+                if (actionSummaryResult.Item2 != 0)
                 {
                     this.Log().Warn(@"
 If a package uninstall is failing and/or you've already uninstalled the
@@ -973,7 +978,8 @@ this option only as a last resort.
             return packageUninstalls;
         }
 
-        private int report_action_summary(ConcurrentDictionary<string, PackageResult> packageResults, string actionName)
+        //TODO once project upgraded to .Net 4.8, switch return type to (int successes, int failures, int warnings, int rebootPackages)
+        private Tuple<int,int,int,int> report_action_summary(ConcurrentDictionary<string, PackageResult> packageResults, string actionName)
         {
             var successes = packageResults.or_empty_list_if_null().Where(p => p.Value.Success && !p.Value.Inconclusive);
             var failures = packageResults.Count(p => !p.Value.Success);
@@ -1041,7 +1047,7 @@ The recent package changes indicate a reboot is necessary.
                 }
             }
 
-            return failures;
+            return new Tuple<int, int, int, int>(successes.Count(), failures, warnings, rebootPackages);
         }
 
         public virtual void handle_package_uninstall(PackageResult packageResult, ChocolateyConfiguration config)