[DRE-maint] Ruby package naming conventions

[Bryan McLellan]

For pure ruby libraries I've been using libpackage-ruby as the virtual
package and libpackage-ruby1.[8,9] for the version specific packages.

Erubis while essentially a library contains a binary package. I don't
know that anyone would use it as an individual package. Is it DRE
policy in this case to name it 'erubis' or 'liberubis-ruby'?

I'll soon be packaging ohai, which is used as a binary as often as a
library. irb, and ri both provide package1.x versions, mongrel does
not. Is it policy to build packages with 1.8 and .19 versions?

Bryan