Factored out common error messages.
Authorization checks implemented for the '/agent' and '/agent/list' interfaces.  #44
Authorization checks implemented for the '/call/*' interfaces.  #44
Factored out JSON formatted error messages to Response.Error_Messages.
Factored out 'No' (permissions).
Authorization checks implemented for the '/debug/*' interfaces.  #44
Authorization checks implemented for the '/notifications' interface.  #44
Style: Fixed indentation and line length.
Log CORS preflight requests.
s/Public_User_Information/Public_User_Identification/ - we are only using this configuration flag to make user names and OpenID URL's public.  #44
Made 'Public_User_Identification' available as a function in package Alice_Configuration.  #44
Implemented a dispatcher for AWS which requires authentication information.  #44
Transformed package Alice_Handlers to a nice, easily readable routing table.  This should ensure that authentication requirements are specified for all interfaces.  #44
Style fixes.