delete old versions bug fix
fixed data-main attr regex issue
refine require.js regex
add Travis CI
update package.json with node engine requirement
add tests for updating css img assets
add manual test environment
added config options to delete old but keep original - fixed #6, needs tests
add manual testing env
clean up lib dir
break keepOriginalAndOldVersions into separate options
keep legacy keepOriginalAndOldVersions option
update README with new deletion options