Get deployments working from Octopus to nuget.org

1) remove build.ps1 from the existing nuspec
2) setup octopus to publish the nupkg to nuget.org
    - use answer from [StackOverflow](http://stackoverflow.com/q/23317526/124069) (if it ever get's answered)

_note: deployments should support `-alpha`, `-beta`, and `production` if we can get a pipeline setup nicely in Octopus's 'Promote To'_
