Add code sample and result image for LineHeightSpan

     * Default implementation of the {@link LineHeightSpan}, which changes the line height of the

     * attached paragraph.

     * <p>

     * LineHeightSpan will change the line height of the entire paragraph, even though it

     * For example, a paragraph with its line height equal to 100px can be set like this:

     * <pre>

     * SpannableString string = new SpannableString("This is a multiline paragraph. This is a multiline paragraph.");

     * string.setSpan(new LineHeightSpan.Standard(100), 0, string.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);

     * </pre>

     * <img src="{@docRoot}reference/android/images/text/style/lineheightspan.png" />

     * <figcaption>Text with line height set to 100 pixels.</figcaption>

     * <p>

     * Notice that LineHeightSpan will change the line height of the entire paragraph, even though it

     * covers only part of the paragraph.

     * </p>

     */