[configure] reorganize sections

configure.in

@@ -214,26 +214,6 @@ if test "$OCAMLYACC" = no ; then
         AC_MSG_ERROR(Cannot find ocamlyacc.)
 fi
 
-#################################################
-# Check for other (optional) tools/libraries    #
-#################################################
-
-new_section "configure optional tools and libraries"
-
-AC_CHECK_PROG(OCAMLDOC,ocamldoc,ocamldoc,no)
-if test "$OCAMLDOC" = no ; then
-  AC_MSG_RESULT(ocamldoc discarded not present)
-else
-        OCAMLDOC="$OCAMLFIND ocamldoc"
-fi
-
-AC_CHECK_PROG(OCAMLMKTOP,ocamlmktop,ocamlmktop,no)
-if test "$OCAMLMKTOP" = no ; then
-  AC_MSG_RESULT(Cannot find ocamlmktop: toplevels cannot be built.)
-else
-        OCAMLMKTOP="$OCAMLFIND ocamlmktop"
-fi
-
 # ocamlcp
 AC_CHECK_PROG(OCAMLCP,ocamlcp,ocamlcp,no)
 if test "$OCAMLCP" = no ; then
@@ -242,11 +222,8 @@ else
         OCAMLCP="$OCAMLFIND ocamlcp"
 fi
 
-AC_CHECK_PROG(OTAGS,otags,otags,)
-
-##############
-# ocamlgraph #
-##############
+# ocamlgraph
+############
 
 AC_MSG_CHECKING(for ocamlgraph)
 
@@ -281,6 +258,28 @@ else
   AC_MSG_RESULT(found)
 fi
 
+#################################################
+# Check for other (optional) tools/libraries    #
+#################################################
+
+new_section "configure optional tools and libraries"
+
+AC_CHECK_PROG(OCAMLDOC,ocamldoc,ocamldoc,no)
+if test "$OCAMLDOC" = no ; then
+  AC_MSG_RESULT(ocamldoc discarded not present)
+else
+        OCAMLDOC="$OCAMLFIND ocamldoc"
+fi
+
+AC_CHECK_PROG(OCAMLMKTOP,ocamlmktop,ocamlmktop,no)
+if test "$OCAMLMKTOP" = no ; then
+  AC_MSG_RESULT(Cannot find ocamlmktop: toplevels cannot be built.)
+else
+        OCAMLMKTOP="$OCAMLFIND ocamlmktop"
+fi
+
+AC_CHECK_PROG(OTAGS,otags,otags,)
+
 # apron
 ########