* src/twaalgos/hoa.cc: Output do not output "unambiguous" if the
automaton is deterministic. Add option "v" to cancel this restriction,
and also output "no-univ-branch".
* src/twaalgos/hoa.hh: Document the "v" option.
* src/tests/readsave.test: Test it.
* src/tests/unambig.test: Adjust for unambiguous not being output
if the automaton is deterministic.
* src/bin/common_aoutput.cc, NEWS: Document it.
* doc/org/hoa.org: Add a summary table about how properties are handled.
* src/twa/twa.hh (prop_deterministic): Setting this should also
set the unambiguous property.
* src/twaalgos/isunamb.cc: Simplify the property check.