idviews: Display the list of hosts when using --all

Enumerating hosts is a potentially expensive operation (uses paged
search to list all the hosts the ID view applies to). Show the list
of the hosts only if explicitly asked for (or asked for --all).
Do not display with --raw, since this attribute does not exist in
LDAP.

Part of: https://fedorahosted.org/freeipa/ticket/3979
extdom: add support for new version

Currently the extdom plugin is basically used to translate SIDs of AD
users and groups to names and POSIX IDs.

With this patch a new version is added which will return the full member
list for groups and the full list of group memberships for a user.
Additionally the gecos field, the home directory and the login shell of a
user are returned and an optional list of key-value pairs which
currently will contain the SID of the requested object if available.

https://fedorahosted.org/freeipa/ticket/4031