Added provider settings for Ziggo and Virgin Media

We (Liberty Global) would like to extend the automatic configuration support with settings for Ziggo (The Netherlands) and Virgin Media (UK). You can validate these settings at:

https://www.ziggo.nl/klantenservice/internet/e-mail/imap/

http://help.virginmedia.com/system/selfservice.controller?CONFIGURATION=1001&PARTITION_ID=1&TIMEZONE_OFFSET=&USERTYPE=1&VM_CUSTOMER_TYPE=Cable&CMD=VIEW_ARTICLE&ARTICLE_ID=2743