filtering pt1

nodes filter, but not edges
also, test filter set is only for the school years…the other checkboxes
aren’t turned on yet
- it’s probably nicer to programmatically render both the network
details table and the filter box div…if we have time.
filtering pt 2

edges filter too now.  more info in process book.
update heat map data
filter progress
filter working, updated exercise csv

filter may have a minor bug - sometimes not all the same points come
back after you turn them back on.  but i can’t quite figure it out.
exercise csv now rounds to nearest integer…decimal values are
inappropriate as it’s a measure of days/week and we just want 1-7
Merge branch 'filter-box'

Conflicts:
	andrew/main.css
	andrew/main.js