Adding ability to disconnect user's orcid profile

With this commit, it is possible for a site administrator to
disconnect a user's orcid profile. This is particularly helpful for
the development and QA process, but could be helpful for other
scenarios as well (i.e. a user associated with the wrong Orcid).
Merge pull request #159 from ndlib/adding-ability-to-disconnect-orcid-profile

Adding ability to disconnect user's orcid profile