Panels to just have a collapse option?

[andrewdavidcostello]

Is it possible for this to be added in, not sure whether it would be a headerless panel or a separate collapse component but it would be really useful to have it either way so you can have a headerless collapsible panel.

For example I have a header for a section with some icons as buttons to trigger the panel:

            <h4>
                Notes
                <a class="pull-right">
                    <span class="glyphicon glyphicon-plus"
                          v-on="click: showNoteForm = !showNoteForm"
                    ></span>
                </a>
            </h4>

            <panel is-open="{{ showNoteForm }}">
                Test
            </panel>