Add tracking of WWT usage for planet parade

[Carifio24]

This PR is a server-side implementation of the functionality requested in cosmicds/planet-parade#60. This primarily consists of model and endpoint updates to add in several new fields, which are:

• wwt_time_reset_count: How many times the user reset the WWT time
• wwt_reverse_count: How many times the user changed whether or not time is reversed
• wwt_play_pause_count: How many times the user pressed the play/pause button
• wwt_speedups: A list of numbers which records the time rate after each time the user presses the speedup button
• wwt_slowdowns: A list of numbers which records the time rate after each time the user presses the slowdown button
• wwt_rate_selections: A list of numbers which records time rates selected from the "More Speed Controls" option
• wwt_start_stop_times: The initial and final times on the WWT clock recorded between each update sent to the database. This isn't any sort of interval as these times are fundamentally unrelated.

Additionally, this adds an extra created field to each entry. This will be set once on the entry creation. Thus we have a sense of when the user first visited the app as well as the last time that their entry was updated.