Final code iteration 2

Removed: Year Slider  (just hid using CSS).
Removed: Max and Min buttons (just experimenting).
Fixed: Incorrect tooltip information on scatterplot after selecting
"Sold" radio button.
Added: tooltips to the bulletgraph.

Known issues:
1) Only plotting ~1k "Sold" listings.
2) Plots of "Sold" Listings are missing numbers before and after the
details on tooltips. (For instance: it might show "Price: $405,2"  or
"Zip: 2118")
3) Bullet graph can appear longer/larger for smaller numbers between
zip codes, due to it calculating the relative size of each zip code's
stats. (Also, the max always looks to be the same amount between zip
codes because it always takes up the entire width of the container.)