ignore garbage
use a different 4SQ account for crawling timeline
don't track screenshot script
selectively hide category feature

Also, get the correct argument for raw_feature depending of whether we want
to use LMNN ground metric or not
close thread after each pass
get a list of user who answer recently
keep track of raw number of visitors to calculate appropriate weights
handle user with answers in several cities
handle circle in gold region
deal with empty results
save complete list of venues
make a copy of user column and use zscore feature
take care of empty category