The vcenter provider allow one to use the `VMWARE_TEST_PLATFORM` to
manually select a test platform. The test platforms are:
- `govcsim`
- `static`
- and `worldstream`.
Before this commit, the `govcsim` value was ignored.
Example:
```shell
$ VMWARE_TEST_PLATFORM=govcsim ansible-test integration --python 3.7 needs/target/prepare_vmware_tests/
```
* Move ansible-test units code into separate dir.
* Fix --explain on "code smell" sanity tests.
* Add --strict-markers to pytest invoctaion.
* Fix classification of units code changes.
* Cache ansible version lookup.
* Fix method of determining ANSIBLE_ROOT.
* Clean up based on PyCharm inspections.
* Generate minimal PKG-INFO without setup.py.
* Use ANSIBLE_LIB_ROOT where possible.
* Use import instead of subprocess to get version.
* Fix install layout type.
* Correct required paths message for installs.
* Update list of files copied during delegation.
* Fix ansible-test entry point.
* Fix pylint issue.
* Fix version lookup on Python 2.x.
* Fix pylint issue.
* Remove unwanted print statement.
* Relocate module validator code and tests.
* Fix validate-modules entry point and imports.
* Fix paths and test entry points.
* Fix up unit tests.
* Fix shebang and execute bit.
* Relocate ansible-only sanity tests.
* Get "code smell" sanity tests from multiple dirs.
- `test/lib/ansible_test/_data/sanity/code-smell/` - General purpose tests used for both Ansible and Ansible Collections.
- `test/sanity/code-smell/` - Tests specific to Ansible, will not be used for Ansible Collections.
