PSA: `cabal update` command needs manual unsticking

[Donn Cave]

Quoth Nathan Collins <nathan.collins at gmail.com>,

> I had some ~/.cabal/packages/hackage.haskell.org/00-index.* files, but
> not any 01-index.* files, and running `cabal update` didn't change
> that.

I see this when using hackage.fpcomplete.com, rather than hackage.haskell.org.

(The latter is very slow for me, and sometimes fails -
  $ cabal update
  Downloading the latest package list from hackage.haskell.org
  dieVerbatim: user error (cabal: '/bin/curl' exited with an error:
  curl: (18) transfer closed with 29508193 bytes remaining to read
  )$ 
)

	Donn