ubi-utils cleanup

[Artem Bityutskiy]

Hi Frank, Alex, Andreas,

since UBIFS gets tried more, people start using ubi-utils more, and I
got several feed-backs about how untidy mtd-utils,git is, and ubi-utils
are untidy as well.

May you please help me cleaning them up a little? We should re-structure
the repo a bit to start of. I've added few ideas into the ubi-utils/TODO
file.

First of, we should separate out UBI tests from ubi-utils and move them
to tests/ubi-tests. Then we should separate-out the tools which are
NAND-related - indeed, what do they do in ubi-utils? They should go to
nand-tools, and stuff like nanddump and nandwrite should go to
nand-tools as well.

Since most of the stuff in ubi-utils were make by your team, I kindly
ask you to help with re-structuring them.

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)