Return also exact matches besides all suggestions

"_getSuggestions" returned all the suggestions from the server, which
are composed by exact matches and partial matches. Now the exact matches
are also returned on their own parameter. This will be used by the
button to confirm a share.

Note that until now the order of the suggestions was "exact users,
partial users, exact groups, partial groups, exact..."; this commit also
changes that order to become "exact users, exact groups, exact...,
partial users, partial groups, partial...". This is not a problem, as
the suggestions were used in the autocomplete dropdown, and this new
order is arguably better than the old one, as all exact matches appear
now at the beginning.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>