[MERGE][Trivial] Update automatic plugin management errors

[John Arbash Meinel]

John Arbash Meinel has voted resubmit.
Status is now: Resubmit
Comment:
I believe we always put the _fmt variable *before* __init__.

And for CommandAvailableInPlugin, why do you have to re-implement 
__str__. It seems like you could just do:
class CommandAvailableInPlugin(StandardError):

     internal_error = False

     _fmt = ('%(cmd_name)r is not a standard bzr command.\n'
             'However, the following official plugin  provides this 
command: %(plugin_name)s\n'
             'You can install it by running: bzr install-plugin 
%(plugin_name)s\n'
             )

     def __init__(self, cmd_name, plugin_metadata, provider):

         self.plugin_metadata = plugin_metadata
         self.cmd_name = cmd_name
         self.provider = provider
         self.plugin_name = plugin_metadata['name']
         self.plugin_url = plugin_metadata['url']


Also, if 'install-plugin' is not in bzr core, I don't want to have an 
exception in core that is telling people to run that command.

You can always have your plugin patch the _fmt string. Or at least you 
could if you used a normal format string like the rest of the errors. 
(That is *much* cleaner that monkey patching the __str__() function at 
run time.)


For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C2422be180805260006l339ece00wbc189ca807f6f1b9%40mail.gmail.com%3E