we always have a model now
push up the loaded target checking
keep track of AR objects we've made as we walk the tree

Remove duplicate removal code because we avoid adding duplicates as we
walk the tree the first time
the parent hash keeps the records unique already
remove useless code

turns out that the activerecord object will always have the same id as
the row from which it was constructed
remove dead code
Some fixes in docs [ci skip]

Update a link to point to right section in api docs

Fix a typo
Fix a writing mistake

A small mistake found in the line of ```The default error is "can't be empty"``` for ```:presence``` helper. ```empty``` word changed to ```blank```.
Merge pull request #12512 from sbagdat/patch-1

Fix a writing mistake
Merge pull request #12507 from malavbhavsar/doc_patch

Some fixes in docs [ci skip]
Merge pull request #11791 from versioncontrol/includes_with_persistent_select

Includes with persistent select, fixes #11773
Drop unused iterator var
Change `map` to `map!` to save extra array creation on new array
`Relation#count` doesn't use options anymore.
Merge pull request #12516 from vipulnsward/drop_var

Drop unused iterator var
Merge pull request #12517 from vipulnsward/destructive_map_am

Change `map` to `map!` to save extra array creation on new array
Merge pull request #12493 from drodriguez/patch-1

Keep code consistent with previous code blocks.
Merge pull request #12491 from shamanime/patch-1

Fix wrong variable name used in the select_day method documentation
Make logging to stdout work again with implicit `development` env
Merge pull request #12514 from schuetzm/stdout-logging-with-implicit-development-env

Make logging to stdout work again with implicit `development` env