motivated simply by a desire to be able to identify 'noderoot' directories for
debugging and testing, the confwiz now writes an 'accountname' files based on
what account was used when the node was configured. this is not currently read
by or used by any code in the system, but helps identify directories from testing.
at one point I'd thrown in a 'str' since fuse api bits required a str instance
but tahoe returns unicode objects from its json parsing. that, naturally
enough should really be a utf8 encoded str of the unicode object...
1. changed the node's exit-on-error behaviour. rather than logging debug and
then delegating to self for _abort_process() instead simply delegate to self
_service_startup_failed(failure) to report failures in the startup deferred
chain. subclasses then have complete control of handling and reporting any
failures in node startup.
2. replace the convoluted wx.PostEvent() glue for posting an event into the
gui thread with the simpler expedient of wx.CallAfter() which is much like
foolscap's eventually() but also thread safe for inducing a call back on the
gui thread.
in certain cases (e.g. the node.pem changed but old .furls are in private/)
the node will abort upon startup. previously it used os.abort() which in these
cases caused the mac gui app to crash on startup with no explanation.
this changes that behaviour from calling os.abort() to calling
node._abort_process(failure) which by default calls os.abort(). this allows
that method to be overridden in subclasses.
the mac app now provides and uses such a subclass of Client, so that failures
are reported to the user in a message dialog before the process exits.
this uses wx.PostEvent() with a custom event type to signal from the reactor
thread into the gui thread.
the confwiz now uses socket.gethostname() if a 'nickname' file doesn't already
exist, and passes that nickname into the 'record_install' method on the backend,
so that the moniker can be recorded in the system table.
