Add extra bbp_breadcrumb wrapper args

[netweb]

Add additional before and after wrappers for breadcrumbs

Introduces 'crumbs_before' & 'crumbs_after' bbp_breadcrumb $args

Existing behavior would not let you correctly target each element with the existing 'before' and 'after' $args

eg. Existing behavior

function custom_bbp_breadcrumb() {
  $args['before'] = '<ul><li>';
  $args['after'] = '</li></ul>';
  return $args;
}

add_filter('bbp_before_get_breadcrumb_parse_args', 'custom_bbp_breadcrumb' );

<ul>
    <li>
        <a href="http://example.com/" class="bbp-breadcrumb-home">Home</a>
        <span class="bbp-breadcrumb-separator"> / </span>
        <a href="http://example.com/forums/" class="bbp-breadcrumb-root">Forums</a>
        <span class="bbp-breadcrumb-separator"> / </span>
        <a href="http://example.com/forums/forum/test-forum/" class="bbp-breadcrumb-forum">Test Forum</a>
        <span class="bbp-breadcrumb-separator"> / </span>
        <span class="bbp-breadcrumb-current">Test Topic</span>
    </li>
</ul>

eg. New behavior

function custom_bbp_breadcrumb() {
  $args['before'] = '<ul>';
  $args['after'] = '</ul>';
  $args['crumbs_before'] = '<li>';
  $args['crumbs_after'] = '</li>';
  return $args;
}

add_filter('bbp_before_get_breadcrumb_parse_args', 'custom_bbp_breadcrumb' );

<ul>
    <li>
        <a href="http://example.com/" class="bbp-breadcrumb-home">Home</a>
        <span class="bbp-breadcrumb-separator">/</span>
    </li>
    <li>
        <a href="http://example.com/forums/" class="bbp-breadcrumb-root">Forums</a> <span class="bbp-breadcrumb-separator">/</span>
    </li>
    <li>
        <a href="http://example.com/forums/forum/test-forum/" class="bbp-breadcrumb-forum">Test Forum</a>
        <span class="bbp-breadcrumb-separator">/</span>
    </li>
    <li>
        <span class="bbp-breadcrumb-current">Test Topic</span>
    </li>
</ul>

Related: ​http://bbpress.trac.wordpress.org/ticket/1821

[johnjamesjacoby]

(In [4332]) Breadcrumb:

• More flexible HTML output for breadcrumb.
• Adds ability to modify HTML before/after separator, current, and each crumb.
• Hat-tip netweb for inital patch.
• Fixes #2009.