Minor cleanups and usability improvements

Author: guillaume-vantroeyen

src/main/scala/com/decisionbrain/cplex/cp/CpModel.scala

@@ -18,7 +18,7 @@ import ilog.cp.IloCP
  *
  * @param name is the name of the constraint programming model
  */
-case class CpModel(name: String=null) extends Modeler {
+class CpModel(val name: String=null) extends Modeler {
 
  val cp: IloCP = {
  val iloCP = new IloCP()

src/main/scala/com/decisionbrain/cplex/cp/IntervalVar.scala

@@ -17,7 +17,7 @@ import ilog.concert._
  */
 class IntervalVar(v: IloIntervalVar)(implicit model: CpModel) extends Addable {
 
- def canEqual(a: Any) = a.isInstanceOf[IntervalVar]
+ def canEqual(a: Any): Boolean = a.isInstanceOf[IntervalVar]
  override def equals(that: scala.Any): Boolean = {
  that match {
  case that: IntervalVar => that.canEqual(this) && this.hashCode() == that.hashCode()

src/main/scala/com/decisionbrain/cplex/mp/MpModel.scala

@@ -23,7 +23,7 @@ import ilog.cplex.{IloCplex, IloCplexMultiCriterionExpr}
 
  * @param name is the name of the model
  */
-case class MpModel(name: String=null) extends Modeler {
+class MpModel(val name: String=null) extends Modeler {
 
  val cplex: IloCplex = {
  val iloCplex = new IloCplex()