[rfc] bzr-colo into core

[Alex Lewis]

Hi,
  I'm a Bazaar beginner but I've been following Bazaar 
  for a while and have enjoyed using it very much so far. 
  I've been trying to use Bazaar regularly with the aim 
  to convert my work colleges. In fact I now use version 
  control (Bazzar) a lot for local files simply because 
  Bazaar lets me do it. Ever since I found (and understood!)
  the colo plugin and its workflow I must admit I thought it 
  was brilliant and consequently wondered why it wasn't 
  *the* Bazaar "model". So this suggestion certainly gets 
  my +1 :)

  IMHO one important thing I think *must* be added to this 
  functionality is auto-(un)shelving of uncommitted changes
  when switching branches. It is the only thing I think 
  currently lets down the colo plugin.

  Hope you don't mind me posting.

Thanks,
Alex