[PATCH 0 of 2 RFC] forward current bookmark on hg update

[Idan Kamara]

1. if you're currently updated to a bookmark and you try to 'hg update'
(e.g. after a pull), the bookmark won't move:

  $ hg glog
  o  changeset:   1:e6a79fe2dd00
  |
  @  changeset:   0:bb12bb026c04
     bookmark:    foo

  $ hg upd
  $ hg glog
  @  changeset:   1:e6a79fe2dd00
  |
  o  changeset:   0:bb12bb026c04
     bookmark:    foo

this changes the behaviour to:

  $ hg upd
  $ hg glog
  @  changeset:   1:e6a79fe2dd00
  |  bookmark:    foo
  |
  o  changeset:   0:bb12bb026c04

2. unbundle currently does this behind your back, I'm not sure why this was
decided but it felt unintuitive to me so I changed that too. instead you should
'hg upd' after unbundling (as suggested by the output) to move the bookmark.