Modified dialog to use sections.
    
    The IPA.dialog has been modified to store sections instead of fields.
    If there is no sections specified, it will create a default section.
    
    The adder dialog for automount map has been modified such that the
    fields related to indirect map are stored in a section which will
    only be visible when the map type is set to indirect.
    
    The adder dialog for host has been modified such that it uses a
    custom section for hostname and DNS zone and standard section for
    the other fields.
    
    Ticket #1394