Meta issue of release blockers for a 7.x-2.0 release

I looked at the D7 issues and I think it's down to these three bugs.

• #2115873: GUEST ACCESS login error
• #1902088: Notice: Undefined variable: _SESSION in _securesite_guest_login()
• #1802772: Custom message for HTML log-in form

This feature request looks pretty close so hopefully it can be included too.
#1454468: Integration with Drush