correct javadoc errors in Matrix3f and Quaternion

jme3-core/src/main/java/com/jme3/math/Matrix3f.java

@@ -1161,7 +1161,7 @@ public final class Matrix3f implements Savable, Cloneable, java.io.Serializable
      *  0.0  1.0  0.0
      *  0.0  0.0  1.0
      * ]
-     * <pre>
+     * </pre>
      *
      * @return the string representation of this object.
      */

jme3-core/src/main/java/com/jme3/math/Quaternion.java

@@ -309,7 +309,8 @@ public final class Quaternion implements Savable, Cloneable, java.io.Serializabl
 
     /**
      * <code>toAngles</code> returns this quaternion converted to Euler rotation
-     * angles (x,y,z) aka (pitch, yaw, roll).<br/>
+     * angles (x,y,z) aka (pitch, yaw, roll).
+     *
      * Note that the result is not always 100% accurate due to the implications of euler angles.
      * @see <a href="http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToEuler/index.htm">http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToEuler/index.htm</a>
      *