Add support for setting/adding arbitrary attributes

This introduces 2 new params: --setattr and --addattr

Both take a name/value pair, ala:

ipa user-mod --setattr=postalcode=20601 jsmith

--setattr replaces or sets the current attribute to the value
--addattr adds the value to an attribute (or sets a new attribute)

OptionsParser allows multiple versions of this, so you can have multiple
setattr and addattr, either for the same attribute or for different
attributes.

ipa user-mod --addattr=postalcode=20601 --addattr=postalcode=30330 jsmith

Values are silent dropped if either of these on an existing param:

ipa user-mod --setattr=givenname=Jerry jsmith

Is a no-op.

0 files changed, 0 insertions, 0 deletions