* src/kripke/Makefile.am, src/saba/Makefile.am,
src/sabaalgos/Makefile.am: Use $(VISIBILITY_CXXFLAGS).
* src/kripke/fairkripke.hh, src/kripke/kripke.hh,
src/kripke/kripkeexplicit.hh, src/kripke/kripkeprint.hh,
src/saba/explicitstateconjunction.hh, src/saba/saba.hh,
src/saba/sabacomplementtgba.hh, src/saba/sabastate.hh,
src/saba/sabasucciter.hh, src/sabaalgos/sabadotty.hh,
src/sabaalgos/sabareachiter.hh: Mark exported symbols
with SPOT_API.