Add the ability to specify the maximum size of the texture atlas

[nesja]

Describe the project you are working on:
I am working on a project that uses a texture atlas and I have plans to support HTML5 and mobile devices

Describe the problem or limitation you are having in your project:
When import images as textureAtlas, there are no settings for the size of the resulting atlas, so with a large number of images a huge atlas is created that doesn't work in HTML5.

Describe the feature / enhancement and how it helps to overcome the problem or limitation:
I propose adding the maximum size property of the atlas to the import settings. If the size is exceeded, the atlas will be created as several image files that don't exceed the maximum size. This functionality allows to get an atlas that is suitable for the desired platform. It will also be possible to create an atlas once for all project images and easily recreate it if the images change.

Describe how your proposal will work, with code, pseudocode, mockups, and/or diagrams:

If this enhancement will not be used often, can it be worked around with a few lines of script?:
I think it will be a useful feature, however it is possible that a few lines of code are enough, but my understanding of the internal process of creating an atlas is limited.

Is there a reason why this should be core and not an add-on in the asset library?:
Size is one of the basic properties of created atlas, on which project support on some platforms depends (I'm not sure what limits are on different platforms and hardware, so I would prefer to use a minimum size of atlas)