GC cleanup

[markples]

• Rename transfer_regions to transfer_regions_from
• Include size in dprintf in get_region_info
• Move decommit dprintf nearer to the relevant code
• Clarify "regions" vs "region units" in dprintfs
• [STRESS_]DYNAMIC_HEAP_COUNT -> [STRESS_]DYNAMIC_ADAPTATION_TO_APP
• Delete a few obsolete comments

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[Maoni0]

please do not merge. I also have some cleanup stuff that I'll include.

[Maoni0]

LGTM. I actually don't have time to do the cleanup changes I wanted to add due to my OOF. but could you please also add a change that rename the DYNAMIC_HEAP_COUNT define to DYNAMIC_ADAPTATION_TO_APP? since DATAS (and I imagine in the future we'd want to adapt to other things other than size) is not just limited to heap count changes.

[cshung]

Can we also remove this obsolete comment?

        // REGIONS TODO: we should reserve enough space at the end of what we reserved that's
        // big enough to accommodate if we were to materialize all the GC bookkeeping datastructures.
        // We only need to commit what we use and just need to commit more instead of having to
        // relocate the existing table and then calling copy_brick_card_table.
        // Right now all the non mark array portions are commmitted since I'm calling make_card_table
        // on the whole range. This can be committed as needed.