create filter class and refactor obligation filter code
cleanup
set up country filter
DRY filters partial
country filter tests
display selected countries' acceptance levels
invalid search query bug caught by tests
cleanup
install bullet (query optimizer gem)
test for excluding "not party to" status
exclude "not party to" status
cleanup
make tests pass
add part and organization filters

+ slight refactoring of filter code
style tweaks
code cleanup
query optimization
Merge branch '909_country_filter' into 911_part_body_filter

Conflicts:
	app/models/filter.rb
extract quotes view to partial
fix ratifications bug