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 generated.  When passed with --help, *only* the help menu is displayed and no config is generated (the same way a module would not run if --help was passed).

Examples:
vol.py -f /root/file1.vmem --profile=WinXPSP2x86 --tz GMT -s
    - Generates a ./volatilityrc with profile, location, and tz saved

vol.py -f /root/file1.vmem --profile=WinXPSP2x86 tz UTC --save pslist
   - Runs pslist, and generates a ./volatilityrc with profile and location saved

python vol.py -f /root/file1.vmem -s -h pslist
   - Only prints the help menu