[DRE-maint] Bug#747489: Package descriptions talks about ruby 1.8

[Christian Hofstaedtler]

Package: ruby-httpclient
Version: 2.3.3-2

Dear Maintainer,

the description for your package ruby-httpclient is:
   HTTP client library for ruby (ruby 1.8 version)

The part "(ruby 1.8 version)" is likely a leftover of the previous
Ruby policy with per-version split packages; please remove it.

Thanks,
  -ch