Disallow anonymous leader feedback

Consensus seems to be against this feature - the primary benefit of
feedback is the ability to contact the supplying leader(s) for more
information. Leaders should be able to be appropriately critical or
complimentary without the need for anonymity (any harsh criticisms can
always be directed to the WSC).

Furthermore, it's not too difficult to guess who supplied the supposedly
"anonymous" feedback.
Add Leader notes, let leaders view participants

Notes may contain things such as rating contingencies, and are only
viewable to leaders and the WSC.

Additionally, this allows leaders to view participant info. This was
always the intention (leaders should be able to view past feedback,
emergency info, etc.). However, testing as an admin never revealed this
issue.