Dynamic Discrete Choice Versions Save

• Minor text edits
• Deleted wercker.yml, which is now obsolete
• Changed DOI in README.md to all versions one

Release that

• includes a link to Rafael Greminger's Julia implementation of the package
• improves CE5
• includes some minor updates of references etc.

Release with minor textual adjustments to trigger a first DOI registration by Zenodo.

First release, of stable version that we have been using in courses for a few years now. Original version: February 8, 2011.