Laravel 5.x compatibility fixes

[mxdfulder]

Most problems were in HasAttributes trait. I've collected missing methods and properties in HasAttributesCompatibility trait and added some missing Interfaces and Exception. All existing tests are passing now for both Laravel 5.x and 8.x version, but it could be some problems with dates casting for old Laravel versions.

[Radiergummi]

Hey @mxdfulder, please don't think I've forgotten! I'm just having mixed feelings about this situation. Copy-pasting Eloquent code to support legacy versions adds quite the maintenance burden on us.
I'd favor adding the compatibility traits to the current revision, release a final version 2 to packagist, then release a new major version 3 with a minimum Laravel 7 requirement. That would mean you'd be locked in on elasticsearch@2.x if you choose to stay on Laravel 5.7, but have the option of upgrading in the future.
Would that work for you?

[mxdfulder]

Hey @mxdfulder, please don't think I've forgotten! I'm just having mixed feelings about this situation. Copy-pasting Eloquent code to support legacy versions adds quite the maintenance burden on us.
I'd favor adding the compatibility traits to the current revision, release a final version 2 to packagist, then release a new major version 3 with a minimum Laravel 7 requirement. That would mean you'd be locked in on elasticsearch@2.x if you choose to stay on Laravel 5.7, but have the option of upgrading in the future.
Would that work for you?

Yes, I think it's reasonable solution

[Radiergummi]

Integrated in v2.3.0. Thanks anyway :)!