Added @since tag

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1178072 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/math/linear/NonPositiveDefiniteLinearOperatorException.java

@@ -30,6 +30,7 @@ import org.apache.commons.math.exception.util.LocalizedFormats;
  * linear operator and {@code x} the "offending" vector.
  *
  * @version $Id$
+ * @since 3.0
  */
 public class NonPositiveDefiniteLinearOperatorException
     extends MathIllegalArgumentException {

src/main/java/org/apache/commons/math/linear/NonSelfAdjointLinearOperatorException.java

@@ -33,6 +33,7 @@ import org.apache.commons.math.exception.util.LocalizedFormats;
  * "offending" vectors, respectively.
  *
  * @version $Id$
+ * @since 3.0
  */
 public class NonSelfAdjointLinearOperatorException
     extends MathIllegalArgumentException {

src/main/java/org/apache/commons/math/linear/RealLinearOperator.java

@@ -47,6 +47,7 @@ package org.apache.commons.math.linear;
  * </dl>
  *
  * @version $Id$
+ * @since 3.0
  */
 public abstract class RealLinearOperator {
     /**