(vc-bzr-dir-state): Use setq rather than set.

(vc-bzr-dir-state): Use setq rather than set.
Use vc-bzr-command rather than the ill defined vc-bzr-command*.
(vc-bzr-command*): Remove both (incompatible) versions.
(vc-bzr-do-command*): Remove.
(vc-bzr-with-process-environment, vc-bzr-std-process-invocation):
Remove by folding into its only caller vc-bzr-command.
(vc-bzr-command): Always set the environment, even when ineffective.
(vc-bzr-version): Minor fix up.
(vc-bzr-admin-dirname): New var.
(vc-bzr-bzr-dir): Remove.
(vc-bzr-root-dir): New fun.
(vc-bzr-registered): Use it.  Add an autoloaded version.
(vc-bzr-responsible-p): Use vc-bzr-root-dir as well.
(vc-bzr-view-log-function): Remove.
(vc-bzr-log-view-mode): New major mode to replace it.
(vc-bzr-print-log): Only activate the old hack if needed.