bzr-whatnow: Workflow wizard/helper

One of the problems that often come up when people switch to Bazaar is the very modular workflow system.

http://bazaar-vcs.org/Workflows is a great tutorial, but requires an internet connection, and you can't always find your way into it; particularly if you are not used to a specific workflow.

In order to address this problem, two features are proposed in this blueprint.

1) bzr whatnow

bzr whatnow adds a command (likely in bzrtools at first) that will query the current environment and provide inline help on the user's workflow depending on local changes, so on. Some sort of "What should I do now?" wizard.

Sample use case:
 adys$~/myproject: bzr whatnow
 You are on a centralized partner workflow. You currently have no uncommitted changes, but your 6 most recent commits have not been pushed. Once you are done, you should push your changes with bzr push.

Setting up the workflow is done on first whatnow run in a project, and/or with a command such as bzr whatnow --setworkflow. This should pop up a list of workflows with a one-line description:
 adys$~/myproject: bzr whatnow
 No workflow has been set.
 Choose which description fits your current workflow best:
 [1] solo: I am alone on this project, tracking changes locally.
 [2] partner: ...

This may not be entirely doable by only querying the local environment. In which case it could query the remote environment, or even ask the user for input on what they want to do.

2) bzr help workflows

bzr help workflows is a help item on workflows which would basically mirror the current wiki online workflow tutorial. It would work like bzr help workflows centralized-partner, and so on.

This feature can be implemented aside of bzr whatnow and there shouldn't be much to do, apart from rewriting the wiki page into the required help format.