Exit gracefully with the usage message if no AppName is given, rather than die with an intimidating stack trace.
Exit gracefully with the usage message if no AppName is given, rather
than die with an intimidating stack trace.

mdavid/manos-spdy,mdavid/manos-spdy,mdavid/manos-spdy,mdavid/manos-spdy,mdavid/manos-spdy,mdavid/manos-spdy,mdavid/manos-spdy