Replace delete by destroy in comments dealing with states.

* src/tgba/succiter.hh, src/tgba/tgba.hh,
src/tgba/tgbabddconcrete.hh, src/tgba/tgbaproduct.hh,
src/tgba/tgbaunion.hh, src/tgbaalgos/bfssteps.hh,
src/tgbaalgos/gtec/ce.cc, src/tgbaalgos/gtec/explscc.hh,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/replayrun.cc,
src/tgbaalgos/scc.cc, src/tgbaalgos/scc.hh: Update comments
to say that we "destroy" a state instead of "deleting" it.

src/tgba/succiter.hh

@@ -1,3 +1,5 @@
+// Copyright (C) 2011 Laboratoire de Recherche et Developpement de
+// l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -85,6 +87,9 @@ namespace spot
     /// in the iteration.  These actually correspond to the same
     /// destination.  It just means there were several transitions,
     /// with different conditions, leading to the same state.
+    ///
+    /// The returned state should be destroyed (see state::destroy)
+    /// by the caller after it is no longer used.
     virtual state* current_state() const = 0;
     /// \brief Get the condition on the transition leading to this successor.
     ///

src/tgba/tgba.hh

@@ -1,4 +1,4 @@
-// Copyright (C) 2009 Laboratoire de Recherche et Développement
+// Copyright (C) 2009, 2011 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2005 Laboratoire d'Informatique de
 // Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
@@ -77,7 +77,7 @@ namespace spot
     /// \brief Get the initial state of the automaton.
     ///
     /// The state has been allocated with \c new.  It is the
-    /// responsability of the caller to \c delete it when no
+    /// responsability of the caller to \c destroy it when no
     /// longer needed.
     virtual state* get_init_state() const = 0;
 
@@ -97,7 +97,7 @@ namespace spot
     ///
     /// \param local_state The state whose successors are to be explored.
     /// This pointer is not adopted in any way by \c succ_iter, and
-    /// it is still the caller's responsability to delete it when
+    /// it is still the caller's responsability to destroy it when
     /// appropriate (this can be done during the lifetime of
     /// the iterator).
     /// \param global_state In a product, the state of the global
@@ -176,7 +176,7 @@ namespace spot
     ///
     /// \return 0 if the projection fails (\a s is unrelated to \a t),
     ///    or a new \c state* (the projected state) that must be
-    ///    deleted by the caller.
+    ///    destroyed by the caller.
     virtual state* project_state(const state* s, const tgba* t) const;
 
     /// \brief Return the set of all acceptance conditions used

src/tgba/tgbabddconcrete.hh

@@ -1,3 +1,5 @@
+// Copyright (C) 2011 Laboratoire de Recherche et Développement
+// de l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2006 Laboratoire d'Informatique de Paris
 // 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
 // Université Pierre et Marie Curie.
@@ -56,7 +58,7 @@ namespace spot
     /// \code
     ///   state_bdd* s = automata.get_init_state();
     ///   some_class some_instance(s->as_bdd());
-    ///   delete s;
+    ///   s->destroy();
     /// \endcode
     bdd get_init_bdd() const;
 

src/tgba/tgbaproduct.hh

@@ -42,7 +42,7 @@ namespace spot
     /// \param left The state from the left automaton.
     /// \param right The state from the right automaton.
     /// These states are acquired by spot::state_product, and will
-    /// be deleted on destruction.
+    /// be destroyed on destruction.
     state_product(state* left, state* right)
       :	left_(left),
 	right_(right)

src/tgba/tgbaunion.hh

@@ -41,7 +41,7 @@ namespace spot
     /// \param left The state from the left automaton.
     /// \param right The state from the right automaton.
     /// These states are acquired by spot::state_union, and will
-    /// be deleted on destruction.
+    /// be destroyed on destruction.
     state_union(state* left, state* right)
       :	left_(left),
 	right_(right)