resolves #18 Add base_dir command line option
add support for version flag to aid with setup
resolves #14 update setup instructions
Enable experimental flag; fix instructions for updating PATH
change terminology to "convert"; switch to uri-* attribute name prefix
revise wording
fix link labels for NOTICE and LICENSE
Merge pull request #23 from DavidGamba/add-base-dir

resolves #18 Add base_dir command line option