Add capability to install IIS on Windows Server 2008

Windows Server 2008 does not use DISM to install IIS and .net framework it uses pkgmgr. The following command will install IIS and all components; only install those components required by Web Adaptor. NOTE: this will also require us to determine the OS so we can call a separate InstallRolesandFeature.bat specific for this OS.

start /w pkgmgr /iu:IIS-WebServerRole;IIS-WebServer;IIS-CommonHttpFeatures;IIS-StaticContent;IIS-DefaultDocument;IIS-DirectoryBrowsing;IIS-HttpErrors;IIS-HttpRedirect;IIS-ApplicationDevelopment;IIS-ASPNET;IIS-NetFxExtensibility;IIS-ASP;IIS-CGI;IIS-ISAPIExtensions;IIS-ISAPIFilter;IIS-ServerSideIncludes;IIS-HealthAndDiagnostics;IIS-HttpLogging;IIS-LoggingLibraries;IIS-RequestMonitor;IIS-HttpTracing;IIS-CustomLogging;IIS-ODBCLogging;IIS-Security;IIS-BasicAuthentication;IIS-WindowsAuthentication;IIS-DigestAuthentication;IIS-ClientCertificateMappingAuthentication;IIS-IISCertificateMappingAuthentication;IIS-URLAuthorization;IIS-RequestFiltering;IIS-IPSecurity;IIS-Performance;IIS-HttpCompressionStatic;IIS-HttpCompressionDynamic;IIS-WebServerManagementTools;IIS-ManagementConsole;IIS-ManagementScriptingTools;IIS-ManagementService;IIS-IIS6ManagementCompatibility;IIS-Metabase;IIS-WMICompatibility;IIS-LegacyScripts;IIS-LegacySnapIn;IIS-FTPPublishingService;IIS-FTPServer;IIS-FTPManagement;WAS-WindowsActivationService;WAS-ProcessModel;WAS-NetFxEnvironment;WAS-ConfigurationAPI

Side note - the following OS's use DISM to install IIS:
- Windows 2012 R2
- Windows 2008 R2 SP1
- Windows 8.1 x64
- Windows 8 x64
- Windows 7 SP1 x64 - I've read that win 7 also uses pkgmgr, but I tested DISM and it worked.

Start by locating the existing DISM-based IIS installation entry point and the InstallRolesandFeature.bat scripts. Compare the Windows Server 2008 requirements with the listed DISM-supported operating systems, then verify that OS detection selects the pkgmgr path and installs only the required Web Adaptor components.

Written by the indexing model from the issue text.