`Date.today` relies on the system's timezone instead of
`Rails.configuration.time_zone`. This can cause tests to fail when we
assert against the date of a record. Just use `Time.zone.today` instead
so that we always follow `Rails.configuration.time_zone`.
This gives us daily fidelity of topic view stats
New table stores a row per topic viewed per day tracking
anonymous and logged on views
We also have a new endpoint `/t/ID/views-stats.json` to get the statistics for the topic.
It wasn't intended that people should be able to earn trust level
3 without participating in public topics. When counting topic
views and likes given/received, don't count private topics.
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.
Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
* cut down on storage of the work Topic, 3 times per row (in 2 indexes)
* only store one view per user per topic
* only store one view per ip per topic
