Enable "access user profiles" for all roles when module is enabled.

Issue Summary

When the openid_provider modules is enabled the user has to give permission to "access user profiles" to all roles for the provider to function. This should happen automatically when you enable the module.

The options are:

1. Simply display a message from hook_install() that the user should go and enable that permission.
2. Show a warning that this permission will be enabled and have the user click OK. Just like when you enable a module with dependencies. (I'm not sure if this is even possible)
3. Always enable the permission and mention it to the user.

I'm thinking that nr. 2 is the most user-friendly and robust solution but I'm not sure if that is possible. Any other ideas?

I'm also pretty sure this is required because people are going to open issues claiming that the provider doesnt work: http://drupal.org/node/251825.