More docs cleanup (#7552)
* More docs improvements.
* timezone: mention which versions of AIX are supported.
(cherry picked from commit 58705d5ac3)
Co-authored-by: Felix Fontein <felix@fontein.de>
* add a new module iso_create
* add elements in argument spec
* remove changelog for new module
* change the path of test file
* comment out pip check task in test case
* comment out install pip in test case
* move pip install task and add skip python2.6