#877 Allow "https : //" to be entered to thwart Outlook's URL munging

[Jeremy Faden]

Outlook email likes to take URLs and make them "safe" by directing the browser through its servers. This breaks Autoplot URIs found in emails, so we often insert extra spaces so that Microsoft will leave them alone.

Autoplot should accept "https : //" and "http : //" in the URI address bar, removing the two spaces automatically.