CamelKolabIMAPXStore: allow retrieval of complete folder info
CamelKolabIMAPXStore: allow retrieval of complete folder info

* usually, imapx_store_get_folder_info_sync() will return
  the CamelIMAPXStore CamelFolderInfo* tree, with the folders
  removed from the data structure which do not match the
  currently-configured folder context (mail, contacts, calendar)
* in order to support folder autodiscovery, we need to allow
  retrieval of the complete folder list, regardless of the
  configured context (this is being used in the collection
  backend)

GNOME/evolution-kolab,GNOME/evolution-kolab