//Add capabilities to author, so he/she can edit...
 function add_theme_caps() {
    // gets the author role
    $role = get_role( 'author' );
    $role->add_cap( 'edit_pages' );
    $role->add_cap( 'edit_published_pages' );
    $role->add_cap( 'edit_posts' );
    $role->add_cap( 'edit_others_posts' );
    $role->add_cap( 'publish_posts' );
    $role->add_cap( 'publish_pages' );
    $role->add_cap( 'edit_published_posts' );
    $role->add_cap( 'edit_published_pages' );
}
add_action( 'admin_init', 'add_theme_caps');