Update node commands which have corresponding bash commands and delete bash command

[seanmccleary]

Many of the node commands were originally written in bash and then ported to node. But the original bash scripts were not deleted, and may have had changes/fixed made to them since then. We need to:

1. Find all node commands that have an equivalent bash command (e.g. "check_migrations")
2. View the git history to see if the bash command has had any changes/fixed made to it after the node version was created
3. Incorporate those changes/fixed into the node version, to bring it to feature parity with the bash version
4. Delete the bash version, so we don't have this duplication going on
5. Ensure documentation is updated to remove references to the bash version