Fix the latest upstream delta for Scala 2.13

```
[warn] 48 deprecations (since 2.13.0)
[warn] 2 deprecations (since 2.13.2)
[warn] 33 deprecations (since 2.13.3)
[warn] 83 deprecations in total; re-run with -deprecation for details
[warn] four warnings found
```

Excellent.

src/main/scala/ostrich/AutomataUtils.scala

@@ -226,7 +226,7 @@ object AutomataUtils {
    * Product of a number of given automata
    * The minimize argument enable minimization of the product automaton.
    */
-  def product(auts : Seq[Automaton],
+  def product(auts : Iterable[Automaton],
               minimize : Boolean = false) : Automaton =
     if (auts forall { _.isInstanceOf[AtomicStateAutomaton] }) {
       productWithMap(auts map (_.asInstanceOf[AtomicStateAutomaton]),
@@ -244,7 +244,7 @@ object AutomataUtils {
    * The minimize argument enable minimization of the product automaton,
    * which should only be used if the returned maps are not used.
    */
-  def productWithMap(auts : Seq[AtomicStateAutomaton], minimize : Boolean = false) :
+  def productWithMap(auts : Iterable[AtomicStateAutomaton], minimize : Boolean = false) :
     (AtomicStateAutomaton, Map[Any, Seq[Any]]) = {
     val idMap = Map[Any, Seq[Any]]().withDefault(s => Seq(s))
     productWithMaps(auts.map((_, idMap)), minimize)
@@ -259,7 +259,7 @@ object AutomataUtils {
    * The minimize argument enable minimization of the product automaton,
    * which should only be used if the returned maps are not used.
    */
-  private def productWithMaps(auts : Seq[(AtomicStateAutomaton,
+  private def productWithMaps(auts : Iterable[(AtomicStateAutomaton,
                                          Map[Any, Seq[Any]])],
                               minimize : Boolean = false) :
     (AtomicStateAutomaton, Map[Any, Seq[Any]]) = {
@@ -288,7 +288,7 @@ object AutomataUtils {
    * The minimize argument enable minimization of the product automaton,
    * which should only be used if the returned maps are not used.
    */
-  private def fullProductWithMaps(auts : Seq[(AtomicStateAutomaton,
+  private def fullProductWithMaps(auts : Iterable[(AtomicStateAutomaton,
                                              Map[Any, Seq[Any]])],
                                   minimize : Boolean = false) :
     (AtomicStateAutomaton, Map[Any, Seq[Any]]) = {
@@ -387,7 +387,7 @@ object AutomataUtils {
    * Form product of this automaton with given auts, returns a new
    * automaton
    */
-  def product(auts : Seq[AtomicStateAutomaton]) : AtomicStateAutomaton =
+  def product(auts : Iterable[AtomicStateAutomaton]) : AtomicStateAutomaton =
     productWithMap(auts, true)._1
 
   /**

src/main/scala/ostrich/BricsTransducer.scala

@@ -679,7 +679,7 @@ class BricsTransducer(val initialState : BricsAutomaton#State,
     return None
   }
 
-  override def toDot() : String = {
+  override def toDot: String = {
     val sb = new StringBuilder()
     sb.append("digraph transducer {\n")
 

src/main/scala/ostrich/OstrichStringFunctionTranslator.scala

@@ -100,7 +100,7 @@ class OstrichStringFunctionTranslator(theory : OstrichStringTheory,
           override def lengthApproximation(arguments : Seq[Term], result : Term,
                                            order : TermOrder) : Formula = {
             import TerForConvenience._
-            implicit val _ = order
+            implicit val o = order
             result >= 0 & result <= 1 &
             ((arguments(0)) <= ind <=> (result === 0))
           }
@@ -118,7 +118,7 @@ class OstrichStringFunctionTranslator(theory : OstrichStringTheory,
           override def lengthApproximation(arguments : Seq[Term], result : Term,
                                            order : TermOrder) : Formula = {
             import TerForConvenience._
-            implicit val _ = order
+            implicit val o = order
             result >= 0 & result <= 1 &
             ((arguments(0)) <= ind <=> (result === 0))
           }
@@ -138,7 +138,7 @@ class OstrichStringFunctionTranslator(theory : OstrichStringTheory,
           override def lengthApproximation(arguments : Seq[Term], result : Term,
                                            order : TermOrder) : Formula = {
             import TerForConvenience._
-            implicit val _ = order
+            implicit val o = order
             ((arguments(0) >= trimLeft + trimRight) &
                result === arguments(0) - (trimLeft + trimRight)) |
             ((arguments(0) < trimLeft + trimRight) &

src/main/scala/ostrich/TransducerTranslator.scala

@@ -210,7 +210,7 @@ object TransducerTranslator {
         new Iterator[IdealInt] {
           def hasNext : Boolean =
             (??? == ProverStatus.Sat)
-          def next : IdealInt = {
+          def next(): IdealInt = {
             ???
             val res = eval(outputC)
             !! (outputC =/= res)