Fixes #832, add debian package and coreclr prereq check to the build.

PR Feedback

scripts/Microsoft.DotNet.Cli.Build.Framework/CurrentPlatform.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Runtime.InteropServices;
+using Microsoft.Extensions.PlatformAbstractions;
+
+public static class CurrentPlatform
+{
+    public static bool IsWindows
+    {
+        get
+        {
+            return RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
+        }
+    }
+
+    public static bool IsOSX
+    {
+        get
+        {
+            return RuntimeInformation.IsOSPlatform(OSPlatform.OSX);
+        }
+    }
+
+    public static bool IsLinux
+    {
+        get
+        {
+            return RuntimeInformation.IsOSPlatform(OSPlatform.Linux);
+        }
+    }
+
+    public static bool IsUbuntu
+    {
+        get
+        {
+            var osname = PlatformServices.Default.Runtime.OperatingSystem;
+            return string.Equals(osname, "ubuntu", StringComparison.OrdinalIgnoreCase);
+        }
+    }
+
+    public static bool IsCentOS
+    {
+        get
+        {
+            var osname = PlatformServices.Default.Runtime.OperatingSystem;
+            return string.Equals(osname, "centos", StringComparison.OrdinalIgnoreCase);
+        }
+    }
+}