Create branch ultrastable

[dread]

• Create a branch named ultrastable that represents latest version of 1.0 as found on dgu
  • Going forward ultrastable will act as stable - 1 (and either ultrastable or stable will be on the rock-solid production systems such as dgu)
• Do not deprecate the stable or metastable branch for the present
• Ask for recommendations on mailing list about best practice for branching (e.g. versioned based versus a simple HEAD versus stable) and how this affects standard operations such as applying bugfixes.
  • For useful discussion of how to do backporting and applying bugfix patches see: ​http://www.python.org/dev/peps/pep-0374/#backport
  • NB: in general do not always have to apply in stable/ultrastable and merge upwards for bugfixes -- can use transplant extension as well.