This allows tests to test these functions without needing to include the test
wrapper directly (now ci/test.lua, formerly test/main.lua). Hopefully this
location is also more stable, similar to other libraries that are already tested.
and add tests. to write test the table_eq function itself, I expose it
in the text env via expect_raw. if we don't want to do this,
alternatives could be:
1. add the test to main.lua itself
2. expose the expect.table_eq function via a test_hooks variable. then
test.lua could require main.lua and access the function via the hook.
may need to update main.lua a bit to ensure it does not run when it
is "require"d