what
        you're changing and to revert changes if necessary.</li>

        <li>You may wish to merge in changes from the trunk. For further
        details see <a href="#branching_update">Merging From the Trunk</a>
        later in this section.

          <ul>
            <li>Make sure that you always commit any local changes to your
            branch before doing a merge. Otherwise it becomes impossible to
            distinguish your changes from those you have merged in. It is also
            impo