fix: add back ShellJS version in --version

This is a small fix for the `--version` flag. This adds back ShellJS
version number, which was re-exposed in PR shelljs/shelljs#1200. This
reverts one of the workarounds added in PR #228.

This also commits package-lock.json to the repo.

Author: nfischer

.gitignore

@@ -6,7 +6,6 @@ lib
 .nyc_output
 coverage
 .shxrc.json
-package-lock.json
 
 # Linux
 *~