Better handling when XML file can't be retrieved

[Rick Barrett]

URLError (usually a 500 from Cineversity) causes CVToolboxError in getXml. Currently just raises an exception to the console, and doesn't allow the toolbox dialog to open.

If we can't get the XML file, there's probably not much point right now in showing the dialog. I'm thinking just a messagebox with a retry option.

[Donovan Keith]

Is there any way to cache the XML file locally? Show something like

"Unable to communicate with the Cineversity server. Tool listings may be out of date. If this issue persists, please report the service outage by going to Help > Report Bug/Idea"

Then load the dialog with the cached XML file. This won't work if it's the first time loading the plugin, but at least it's something. Perhaps for first-time users we include a cached version of the XML in the distribution archive?

[Rick Barrett]

We could, although if we're having trouble contacting Cineversity the authorization and the majority of the installs will fail too.

[Donovan Keith]

3rd party installs should still work. Also, if the dialog doesn't open, people can't report bugs through the help pulldown.

[Rick Barrett]

By the same token, I don't want 500 bug reports because Cineversity was down for a bit.

[Donovan Keith]

Okay:

If this issue persists for more than 24hrs please report the service outage by sending an email to [e-mail]

[Rick Barrett]

Fixed in e1e7e32e8