Initial Bats scaffold (DO NOT MERGE)

[hyperupcall]

The purpose of this PR is to better show the additions that might be made to incorporate Bats, a testing framework for Bash. More information about this PR can be found in this comment.

To run this code, be sure to:

1. Install Bats (see instructions on Bats website)
2. Switch to this branch (this branch adds a git submodule, hyperupcall/bats-all, be sure to update submodules (i think that git submodule update --init should do the trick))
3. Now you can run bats ./tests

When executing Bats, Bats will look for files inside of ./tests that end with .bats. If it sees any, it "executes" it. In this PR, there are two .bats files used to demonstrate a few features of Bats.

[hyperupcall]

@spacewander Hey question separate from this pull request - what do you think about closing pull requests that haven't had activity in 1 year? I wanted to close old pull requests to make it easier to keep track of what might actually be merged, but I wanted to get your OK first

[spacewander]

@spacewander Hey question separate from this pull request - what do you think about closing pull requests that haven't had activity in 1 year? I wanted to close old pull requests to make it easier to keep track of what might actually be merged, but I wanted to get your OK first

LGTM. Let's use the stale action to do it. Robot is more suitable to do this job than human.