Allowing set config path

Lines 125 to 127 in 0503e25

    
           } else { 
        
           	dir = filepath.Join(os.Getenv("HOME"), ".config", "pet") 
        
           }

Would it be possible to have something like os.Getenv("PETCONFIGPATH") for changing where the config file would reside?

	} else {
	dir = filepath.Join(os.Getenv("HOME"), ".config", "pet")
	}