Javadoc: Remove obsolete comments and clarify

src/main/java/org/apache/commons/lang3/exception/ExceptionUtils.java

@@ -439,10 +439,10 @@ static String[] getStackFrames(final String stackTrace) {
      * {@link Throwable} object, decomposing it into a list of
      * stack frames.
      *
-     * <p>The result of this method vary by JDK version as this method
+     * <p>
+     * The result of this method vary by JDK version as this method
      * uses {@link Throwable#printStackTrace(java.io.PrintWriter)}.
-     * On JDK1.3 and earlier, the cause exception will not be shown
-     * unless the specified throwable alters printStackTrace.</p>
+     * </p>
      *
      * @param throwable  the {@link Throwable} to examine, may be null
      * @return an array of strings describing each stack frame, never null
@@ -455,12 +455,12 @@ public static String[] getStackFrames(final Throwable throwable) {
     }
 
     /**
-     * Gets the stack trace from a Throwable as a String.
+     * Gets the stack trace from a Throwable as a String, including suppressed and cause exceptions.
      *
-     * <p>The result of this method vary by JDK version as this method
+     * <p>
+     * The result of this method vary by JDK version as this method
      * uses {@link Throwable#printStackTrace(java.io.PrintWriter)}.
-     * On JDK1.3 and earlier, the cause exception will not be shown
-     * unless the specified throwable alters printStackTrace.</p>
+     * </p>
      *
      * @param throwable  the {@link Throwable} to be examined, may be null
      * @return the stack trace as generated by the exception's
@@ -716,17 +716,19 @@ public static boolean isUnchecked(final Throwable throwable) {
     /**
      * Prints a compact stack trace for the root cause of a throwable
      * to {@code System.err}.
-     *
-     * <p>The compact stack trace starts with the root cause and prints
+     * <p>
+     * The compact stack trace starts with the root cause and prints
      * stack frames up to the place where it was caught and wrapped.
      * Then it prints the wrapped exception and continues with stack frames
-     * until the wrapper exception is caught and wrapped again, etc.</p>
-     *
-     * <p>The output of this method is consistent across JDK versions.
-     * Note that this is the opposite order to the JDK1.4 display.</p>
-     *
-     * <p>The method is equivalent to {@code printStackTrace} for throwables
-     * that don't have nested causes.</p>
+     * until the wrapper exception is caught and wrapped again, etc.
+     * </p>
+     * <p>
+     * The output of this method is consistent across JDK versions.
+     * </p>
+     * <p>
+     * The method is equivalent to {@code printStackTrace} for throwables
+     * that don't have nested causes.
+     * </p>
      *
      * @param throwable  the throwable to output
      * @since 2.0