[Proposal] Changed valid_in to exclude valid_from = to and valid_to = from

[osyo-manga]

Summary

valid_in include valid_from = to and valid_to = from.

Code:  valid_in(from: 02/01, to: 05/01)
Query: from <= valid_to AND valid_from <= to

01/01         02/01         03/01         04/01         05/01         06/01
  |*************|*************|*************|*************|*************|
               ↑                                        ↑
              from(02/01)                                to(05/01)

However, in real-world use cases, you may not want to include valid_from = to and valid_to = from.
e.g. https://github.com/kufu/activerecord-bitemporal/pull/93/files#diff-77aac43b146505859dd74b1fd3e151c0e94174f5abc85475fe1dfba10a5c64bfR513

Proposal

Changed valid_in to exclude valid_from = to and valid_to = from.

Code:  valid_in(from: 02/01, to: 05/01)
Query: from < valid_to AND valid_from < to

01/01         02/01         03/01         04/01         05/01         06/01
  |-------------|*************|*************|*************|-------------|
               ↑                                        ↑
              from(02/01)                                to(05/01)

Also, Range can be passed as an argument.
It behaves differently for (from...to) and (from..to).

Code:  valid_in(02/01...05/01)
Query: from < valid_to AND valid_from < to

01/01         02/01         03/01         04/01         05/01         06/01
  |-------------|*************|*************|*************|-------------|
               ↑                                        ↑
              from(02/01)                                to(05/01)

Code:  valid_in(02/01..05/01)
Query: from < valid_to AND valid_from <= to

01/01         02/01         03/01         04/01         05/01         06/01
  |-------------|*************|*************|*************|*************|
               ↑                                        ↑
              from(02/01)                                to(05/01)

[tmtm]

LGTM 👍

[Dooor]

LGTM 🎉

[osyo-manga]

Thanks for review :)