Rename *RefreshKind::new method into nothing

[GuillaumeGomez]

Fixes #1400.

So now, instead of writing DiskRefreshKind::new() if you don't want to refresh disks information, you will write DiskRefreshKind::nothing().

[softdevca]

I agree with renaming::new() to ::nothing()`. It makes it more clear what will be refreshed.

[afiqzx]

Would ::new_nothing() be better?

Edit: after looking thoroughly the changes, I agree changing it to nothing()

[alice-i-cecile]

How about do_not_refresh?

[Hywan]

Here is another feedback: what about *RefreshKind::none()?

[algesten]

Here is another feedback: what about *RefreshKind::none()?

English is not my first language but spontaneously I had the same thought. A kind feels like it must be paired with none.

[GuillaumeGomez]

@Hywan, @algesten: The "equivalent" method is everything(). I'm not sure whether nothing or none is a better match. With this in mind, do you still think the same?

[GuillaumeGomez]

How about do_not_refresh?

Sounds a bit weird no? It would look like this: RefreshKind::do_not_refresh.