[5.5] Allow where and dynamicWhere to handle arrays

[BrandonShar]

Currently if you pass an array as the value of where, you get strange behavior:

User::whereName(['brandon', 'matt'])->get();
select * from `users` where `name` = 'brandon'

or much worse

User::whereName(['brandon', 'matt'])->whereId(5)->get();
select * from `users` where `name` = 'brandon' and `id` = 'matt'

This PR would assume the user was interested in a whereIn query instead and handle that automatically.

User::whereName(['brandon', 'matt'])->get();
select * from `users` where `name` in ('brandon', 'matt')
// OR
User::where('name', '<>', ['brandon', 'matt'])->get();
select * from `users` where `name` not in ('brandon', 'matt')

[fitztrev]

Related #19126

[taylorotwell]

Holding off for now.

[BrandonShar]

Thanks for taking a look.

Don't know how I missed that PR when I searched around. Thanks for the link @fitztrev