[racket] Ubuntu PPA update for 6.1.1

On 2014-11-10 18:32:27 -0500, Asumu Takikawa wrote:
> I've updated the Ubuntu PPA for v6.1.1:
>   https://launchpad.net/~plt/+archive/ubuntu/racket
>
> It should support precise, trusty, and utopic.
>
> As usual, please let me know if there any packaging bugs.

A few people have reported that they get some errors from Ubuntu's
package manager when upgrading due to file conflicts with the old
version.

If you see the same thing, try uninstalling the old PPA package first
and then re-install. Or you may have luck using the -f option. Do let me
know if neither works.

This is likely caused by some packaging changes I had to make for
v6.1.1, but should probably not happen for the next version. Sorry for
the inconvenience.

Cheers,
Asumu