Rework of riemann-smith for the New Age

- Use riemann/tools common scaffolding (gives us all the default options for
  free)

- Rename script file to `riemann-smith`, to maintain consistency with
  standard tools

- Create a gemspec, so we can actually deploy this thing, along with a
  Gemfile, Rakefile, etc (all the standard Good Shit)
Merge pull request #1 from mpalmer/master

Rework of riemann-smith for the New Age