Gems supporting older versions of ruby

[Keenan Brock]

Hi,

I'm noticing that lots of gems have dependencies very tightly locked down.

The gems work with a newer versions of a dependent gem.

But when the restriction is loosened, the travis build fails.

Bundler is not able to discern a version of the gem that will work for that version of ruby. 

I'm guessing the solution is to add `required_ruby_version` to the gemspec of all the dependent gems. Possibly for all the major versions of the gem too.

e.g.:

mime-type version 1.x supports 1.8.7+

version 2.x requires 1.9.3+

In order to compile under travis and 1.8, the gemspec is pegged to 1.x.

Will I fix things if I get mime-types to add `require_ruby_version` to the gemspec of the latest 1.x and 2.x?

Will rubygems.org take the ruby version into account while looking for the right version?

Will rubygems.org be able to handle missing require_ruby_version in the middle of the versions?

Thanks all,

Keenan