* Demographics page:
* Show percents with up to 1 decimal place of precision.
* On tablets+ align the percent text to the right.
* On photo counts, only include certified active user photos.
* On gender/orientation demographics, pad the remaining "No answer" counts
with the set of users who have no profile_fields set in the database yet.
* Admin certification page:
* Add additional "common rejection reasons"
* Add a confirm prompt when viewing the Rejected list to avoid accidental
approval of previously rejected cert photos.
