add part and organization filters

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

Conflicts:
	app/models/filter.rb
extract quotes view to partial
merge 909_country_filter and resolve
bug with checking if any filters checked before filtering filters
Merge branch 'develop' into 911_part_body_filter
unit tests for document methods
update filter tests
filter other filters test
Merge branch '911_part_body_filter' into develop