refactor(dist): hoist dist::dist into dist

[rami3l]

This is a natural step in the spirit of #3880.

Concerns

• It's time to decide between foo.rs and foo/mod.rs. (I'm slightly inclined towards foo.rs) Split into Style: Decide between foo.rs and foo/mod.rs #3883.

[djc]

• It's time to decide between foo.rs and foo/mod.rs. (I'm slightly inclined towards foo.rs, cc @rbtcollins.)

I still find this still imposes non-trivial cognitive overhead because it means each module appears twice in the directory tree, and I have to decide which one I need to open.

[rami3l]

This is a natural step in the spirit of #3880.

Concerns

• It's time to decide between foo.rs and foo/mod.rs. (I'm slightly inclined towards foo.rs, cc @rbtcollins.)

• It's time to decide between foo.rs and foo/mod.rs. (I'm slightly inclined towards foo.rs, cc @rbtcollins.)

I still find this still imposes non-trivial cognitive overhead because it means each module appears twice in the directory tree, and I have to decide which one I need to open.

@djc Let's continue the discussion at #3883 since it looks not very appropriate to comment on a soon-to-be closed PR :P