stat: add .created, .last_updated, .last_modified to returned namedtuple

[OddBloke]

This introduces access to lastUpdated in the return value, as well as adding ctime and mtime equivalents with the same naming scheme.

[beliaev-maksim]

Looks great, can you please add a deprecation notice for old attributes?

[allburov]

@beliaev-maksim Let's do not do it, it's the standard in other areas and we should keep those fields, it costs nothing to us

[beliaev-maksim]

@allburov
Then it is a confusion to have two fields that do the same. We either deprecate old implicit names or remove newly added

[allburov]

@beliaev-maksim we might add a note about it that ctime is an alias for created field (the same for mtime), but not the deprecation warning, we don't have the plan to remove them

[beliaev-maksim]

@allburov
ok, then let's proceed with the note. I think docstrings and docs will be sufficient for this

[OddBloke]

I've just pushed up updated docstrings, and replaced the one other usage of [cm]time in docs that I could find.

[beliaev-maksim]

looks good, thanks