Disclose that the "my schedule" page is publicly viewable

I just chatted with coltrane about this in IRC. I understand the reasoning behind schedules being public and that many people want this feature, but feel like we need to make sure to disclose that schedules are publicly viewable.

With that in mind, I propose altering the views header in the "my schedule" from:

"List of events at DrupalCon Denver you plan to attend. Please note that registration is still required for entrance to DrupalCon and trainings are sold separately."

to:

"List of events at DrupalCon Denver you plan to attend. Please note that your schedule is publicly viewable. Registration is still required for entrance to DrupalCon and trainings are sold separately."