fix issue where previous table listing was being displayed momentarily even after a new database is chosen.

a little more work to get color assignment working in the case where we have more users than colors.

support more card filtering options such as by database, plus make it possible to indicate and clear the table filter choice.

add css background color options for purple and green and update our user initials colors array to use all the colors.

Fix angular minification issue

update unit test to account for the fact that we changed the query param for specifying the model id.

report the users name as "You" when it's an activity they did themselves, and simplify a couple other things with activity description rendering.

get colors and a couple more things working with activity user initials, fix up formatting for database-sync type activity.

when recording a database-sync activity set the database_id value as well as the model_id value for the activity.

do a little cleanup work on our event processors to make them more robust and fix a small bug in the event tracking for database sync.

adding in the new view tracking code so that we can have an accurate Recents section on the homepage (implements #938)

cleanup the way the ActivityDescription is rendered and use a small react component to wrap that display.

get all of the card filtering by Table stuff working.  formatting is pretty close now on Saved Questions tab.