Added remove_association_no_negative_assoc to config to allow user to…

[Doctor06]

… decide if they want to keep the join when using negative predicates.

Fix issue where negative predicates with associated_collection does not use the correct primary key for subquery.

[Doctor06]

I had failing tests when i tried pulling from master without me making any changes. What do i do when that happens? Those checks that fails are the original failing tests i inherited from just forking.

[scarroll32]

@Doctor06 please try rebasing against master.

[deivid-rodriguez]

@Doctor06 Perhaps context has been lost here and you're no longer interested but master branch should be fully green now, so if you could rebase and fix merge conflicts that'd be awesome!

[scarroll32]

@Doctor06 we would love to make this one of the changes released with the 3.0.0 release

[scarroll32]

This is breaking the not_null predicate.

Removing from 3.0.0 release.

 1) Ransack::Adapters::ActiveRecord::Base negative conditions on HABTM associations removes redundant joins from top query
     Failure/Error: expect(sql).to_not include('LEFT OUTER JOIN')
       expected "SELECT \"articles\".* FROM \"articles\" WHERE ('default_scope' = 'default_scope') AND \"articles\".\...cles_tags\".\"tag_id\" WHERE ('default_scope' = 'default_scope') AND \"tags\".\"name\" = 'Fantasy')" not to include "LEFT OUTER JOIN"
     # ./spec/ransack/adapters/active_record/base_spec.rb:159:in `block (3 levels) in <module:ActiveRecord>'

  2) Ransack::Predicate not_null with association qeury generates a value IS NULL query when assigned false
     Failure/Error: expect(sql).to match /#{field} IS NULL/

       expected "SELECT \"people\".* FROM \"people\" WHERE \"people\".\"id\" NOT IN (SELECT \"people\".\"id\" FROM \"...RE \"comments\".\"id\" IS NOT NULL ORDER BY \"people\".\"id\" DESC) ORDER BY \"people\".\"id\" DESC" to match /"comments"."id" IS NULL/
       Diff:
       @@ -1 +1 @@
       -/"comments"."id" IS NULL/
       +"SELECT \"people\".* FROM \"people\" WHERE \"people\".\"id\" NOT IN (SELECT \"people\".\"id\" FROM \"people\" LEFT OUTER JOIN \"comments\" ON \"comments\".\"disabled\" = 0 AND \"comments\".\"person_id\" = \"people\".\"id\" WHERE \"comments\".\"id\" IS NOT NULL ORDER BY \"people\".\"id\" DESC) ORDER BY \"people\".\"id\" DESC"