Improve tests
- add more unit test cases
- add specific integration test with more cases
Testing shows no major downside to calling .strip() twice in a comprehension vs. using a regular for loop and only calling .strip() once. Going with the comprehension for ease of maintenance and because comprehensions are optimized in CPython.
* Move ansible.compat.tests to test/units/compat/.
* Fix unit test references to ansible.compat.tests.
* Move builtins compat to separate file.
* Fix classification of test/units/compat/ dir.