(#2738) Check installed .NET version installed is at least 4.8

This adds a registry check to chocolatey.console to validate that .Net
4.8 or later is installed. This check is added because Chocolatey CLI
can start to execute but runs into errors when the system has an older
version of .Net framework installed. The check is very early on in the
execution so as to print out a helpful error before any errors due to
incompatibilities with the older .Net version show up.

src/chocolatey.console/Program.cs

@@ -44,6 +44,8 @@ namespace chocolatey.console
     using Console = System.Console;
     using Environment = System.Environment;
     using IFileSystem = infrastructure.filesystem.IFileSystem;
+    using Microsoft.Win32;
+    using chocolatey.infrastructure.platforms;
 
     public sealed class Program
     {
@@ -124,6 +126,8 @@ private static void Main(string[] args)
                     }
                 }
 
+                check_installed_dotnetfx_version();
+
                 if (warnings.Count != 0 && config.RegularOutput)
                 {
                     foreach (var warning in warnings.or_empty_list_if_null())
@@ -370,5 +374,24 @@ you can ignore this warning.
 Or by passing the --skip-compatibility-checks option when executing a
 command.");
         }
+
+        private static void check_installed_dotnetfx_version()
+        {
+            if (Platform.get_platform() == PlatformType.Windows)
+            {
+                const string REGKEY = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\";
+                const int NET48RELEASEBUILD = 528040;
+
+                using (var ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(REGKEY))
+                {
+                    if (ndpKey == null || ndpKey.GetValue("Release") == null || (int)ndpKey.GetValue("Release") < NET48RELEASEBUILD)
+                    {
+                        throw new ApplicationException(
+                            ".NET 4.8 is not installed or may need a reboot to complete installation{0}Install .NET 4.8 and reboot the system"
+                                .format_with(Environment.NewLine));
+                    }
+                }
+            }
+        }
     }
 }