fix unassigned servername, github issue 150 (#153)

Author: robverschoor

SMO_DDL.ps1

@@ -213,7 +213,10 @@ Function GenerateDDL-DB {
 
 	# Get some info on the SQL Server instance to include in the Babelfisn Compass report
 	$SrvResourceTag = "SMO_DDL SQL Server info:" # do not change this string, or the variable name below!
-	$SQLSrvName = $($MyServer.NetName)
+    $SQLSrvName = $($MyServer.NetName)
+	if ($SQLSrvName -eq $null -or $SQLSrvName -eq '') {
+	    $SQLSrvName = $Servername
+	}	
 	Write-Output "`n--SQL Server Information generated by SMO_DDL.ps1 (do not change these lines):`n"  | Add-Content -Path $DDLFilename	
 	Write-Output "DECLARE @srvinfo VARCHAR(MAX)"  | Add-Content -Path $DDLFilename	
 	Write-Output "SET @srvinfo = '$SrvResourceTag $($SQLSrvName):Edition=$($MyServer.Edition)'"  | Add-Content -Path $DDLFilename