ubi branch in mtd-utils repo

[Josh Boyer]

Hi All,

I've added a ubi branch to the mtd-utils repo to give users a
"preview" of the ubi utilities.  This was created from Frank
Haverkamp's repo and the great work he and his team have done.  It
also contains a handful of fixes for 64 bit issues that I just fixed
today.

I intend for this branch to be the main repo for the utilities until
UBI is in the upstream kernel.  At that point, I'll merge the branch
to master and include them with the rest of the MTD utils.

If anyone has issues with this plan, please let me know.

thx,
josh