DOC: Remove all versionchanged / versionadded directives < 1.0.0
**Description**
Remove all `versionchanged` / `versionadded` directives for versions < `1.0.0`

**Checks**
- [x] closes https://github.com/noatamir/pydata-global-sprints/issues/10)
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
thx @iofall