change name 'unique only' to 'unique individuals only'

[LindsayYoung]

Change name 'unique only' to 'unique individuals only'

https://beta.fec.gov/data/receipts

Also since we have a view for individuals, we probably should not set it true by default. that is how the link starts off here

https://beta.fec.gov/data/advanced/

Here is the explanation from the API documentation if you want to reference https://api.open.fec.gov/developers/#!/receipts/get_schedules_schedule_a

[PaulClark2]

I agree. For the All receipts page unique individuals only should not be selected by default.

[jwchumley]

Agreed.