Gets the singleton instance/object of the AppSettings class. 
      Syntax
         
         
            + 
            (
            SMPAppSettings *
            ) 
            
               initializeWithConnection
            
            : 
            (
            SMPClientConnection *
            ) 
            clientConn 
            
               userName
            
            : 
            (
            NSString *
            ) 
            userName 
            
               password
            
            : 
            (
            NSString *
            ) 
            password
         
      
      Parameters
         
         
            - 
               clientConn – 
               Object of SMPClientConnection class
            
 
            - 
               userName – 
               User Name that will be authorised by a predefined security provider
            
 
            - 
               password – 
               Password for that user
            
 
         
       
      Returns
         Returns the instance of the class SMPAppSettings
      Example 1
         SMPAppSettings* appSettings = [SMPAppSettings initializeWithConnection:clientConn userName:"username" password:@"password"];