Automatically save command line options to ./volatilityrc

Hi all,
This contribution adds the ability to use --save or -s to save command line options such as PROFILE and LOCATION to a volatilityrc configuration file in the current directory.  When passed with plugins such as "imageinfo," both the plugin is run and the config file is generate.  When passed with --help, *only* the help menu is displayed and no config is generated (the same way a module wouldn't run if --help was passed).