As a curator I want to "diff" one filter result against another in a new facet

[mjy]

When I start with a query I want to copy the URL, then paste it to a facet to operate like ( A ( AB ) B ) C

• All records in current not in pasted A
• All records in found in both AB
• All records in pasted not in current B
• All records C

[mjy]

Added venn and venn_mode params to all Query::Filter

Add yellow facet (bottom of filters):

Venn ("B" query)

label: Paste the full JSON or Browser URL request of a query for this filter [text input]

Label Mode [Radio buttons]

• Exclude (A not B) (venn_mode=a)
• Intersect (found in A & B) (venn_mode=ab)
• Inverse (B not A) (venn_mode=b)