ruby-curb: new upstream version 0.8.5 (fix FTBFS #720256)

[David Suárez <david.sephirot@gmail.com>]

Hi,

I have updated ruby-curb to a new upstream version.

Some comments:
  * New upstream version
  * Fix test segfault due to the wrong ruby version extension getting loaded
    (Closes: #720256)
  * Add support for curl 7.33.0. This fix a test failing due to some api
    changes in the new curl version

It builds fine on a sid chroot.

Can anyone review and upload it.

Thanks,
  David