Sort files by size before push/pull

[efiop]

[efiop]

Related to #522

[efiop]

Sorry, closed by accident.

[efiop]

No longer relevant with new design. Closing.

[casperdcl]

reopening due to #3594 (comment) and #3594 (comment). Basically:

• slight speed improvement
• reducing whitespace between nested bars
• to implement this, sizes aren't currently available for pull but they'll be required anyway for other thigs (e.g. Add summary to dvc status -c [target]  #3568)

[efiop]

Closing in favor of #3682 , as that will be a better solution overall

[shcheklein]

Closing in favor of #3682 , as that will be a better solution overall

💅 #3682 is not about performance though. Certain scenarios can benefit a lot from sorting by size on download/upload.