Add features related to Trades

[earlejam]

This is a starter issue-- these should receive their own issues if ever pursued.

• Dotted lines (or similar) marking the week a trade happened (divides the glyphs into two halves--before and after the trade). Would probably include only the two teams that were involved in the trade (if focusing on it). Upon hovering on the dotted line, a tooltip would pop up with a summary of the trade, i.e. which players were exchanged. The idea is to see if the team was better before or after the trade (many confounding variables, but a place to start).

• Trade analysis. Hindsight is 20/20. A list of all the trades that happened during the season, and then analysis of who won (could be both or neither), by how much, how much each of the players contributed before and after the trade (imagine a filled line of each player's points each week, and the lines sum to some total area under the curve, compare the each set of players on different charts). A more advanced version would simulate each team's lineup in the scenario where the trade happens and doesn't happen, and based on weekly projections, predict which players would have been started, how many points would have been scored (+ difference), difference in wins/losses as a result (and if that would have affected playoff berth, seeding, potentially the winner).

• Teams may make multiple trades per season--see who did themselves the most harm and who made up the most ground with trades. (Number of trades, difference in total points scored, difference in projected scores with/without).