Useful keep_fn for unmoderated.
Fix issues with use of amqp for SponsorBoxWeights
bidding: Refactor PromotionWeights queries
SponsorBoxWeightings: optimize set_from_weights

It now will do a smart lookup of what Subreddits might be
active, and update only that set.
LiveAdWeights: Cache friendly, non-permacache ads
Organize imports in bidding.py
Serve ad data from LiveAdWeights, not permacache
Search upload: Fix bug in NSFW status of subreddits
Correct duplicate PromotionLog from mis-merge
tdb_cassandra: Resurrect View.get_time_sorted_columns.
gilding: Add some views for stats gathering.
Shard vote_link_qs by last digit of subreddit ID.

This should help with permacache contention.
app_globals: Move queue declarations to setup() etc.

It now relies on ini file configuration.
Function to fetch refund amount from authorize.net
stats.Timer: Add method for getting timer's elapsed time.
Add "days" config type and move MODWINDOW into it.
Drastically reorganize app_globals and time app startup.

This should give us more information on which steps of app startup are
taking the most time so that we can minimize the effects of pushes on
capacity.
app_globals: Clean up imports.
Tighten permissions checking on modmail responses

Prevents users who don't have permission to see a mail
thread from submitting replies to it.
promote.py: No more permacache for get/set_live_promotions