Fix IE failing when authenticating with IdP from main site's /signin

* window.name is used to keep track of where to redirect the user once authentication with the IdP is complete. IE was losing window.name when redirected to the IdP because it was set from within the dialog.
* Set the window.name to auth_with_primary when window.open is called.
* Update WinChan to use the version that allows the setting of window.name