fix: roundup-demo, interactive mode would nuke an existing tracker. Tonu Mikk demonstrated a bug in roundup-demo. When invoked without a tracker home on the command line, it would nuke an existing directory specified interactively. There is still a minor bug. If an invalid home directory is specified, roundup-demo will prompt for the template to use before reporting: Error: Refusing to nuke non-tracker directory: but this doesn't cause data loss so not worth fixing at this time.

try:
    from html import escape as html_escape_  # python 3

    def html_escape(str, quote=False):
        # html_escape under python 3 sets quote to true by default
        # make it python 2 compatible
        return html_escape_(str, quote=quote)
except ImportError:
    # python 2 fallback
    from cgi import escape as html_escape  # noqa: F401