doc: classhelper translation, advanced config w/ roles endpoint Added info on how to translate default title and data-popup-title. Also added advanced config section on deploying a new roles rest endpoint and changing classhelper to use it.

try:
    # Python 3+
    from ssl import SSLError
except (ImportError, AttributeError):
    # Python 2.5-2.7
    from socket import sslerror as SSLError  # noqa: F401