Allow attributes to be set for linkToOwnerProfile()

[kimisgold]

As a theme writer, I'd like to be able to set classes and other attributes for a link to an owner profile. For example, in conjunction with the Groups plugin, I'd like to set an "owner" class on a link to the profile of a group owner.

The linkToOwnerProfile() helper needs to be able to take an array of attributes and values and works if it prints out those attributes and values within the <a> tag.

[kimisgold]

Actually, it might be more helpful to have some way to use Omeka's existing link_to() helper with User Profiles.