Potential workaround for #932: force modal-less UI on IE.

This isn't a great workaround, as it boots the user off the issuer's site
and redirects them to the backpack without an easy way to return to where
they came from, but it's much better than what currently happens. And it
avoids the legal issues involved in delivering a P3P header that makes
the modal issuer flow "just work".
Document Issuer API issue_no_modal
Merge remote-tracking branch 'toolness/issue-932-workaround' into docs

* toolness/issue-932-workaround:
  Potential workaround for #932: force modal-less UI on IE.
Change .issue() docs to reflect force modaless UI on IE
Merge remote-tracking branch 'lars/docs' into development
Merge remote-tracking branch 'upstream/development' into development
Merge pull request #963 from mozilla/chris-resolve-conflict

Chris resolve conflict