### Describe Your Changes
Christmas is early and you get the first present in the shape of
spelling fixes.
Sorry for the big amount :)
### Checklist
- [x] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
Also tried to make it catch "Authorisation" in the future, fixed a lot
of other misspells along the way, but didn't make it catch
"Authorisation" anyway.
- Fix misspelled "Authorization" header name
- Fix misspelled "organization"
- Fix more misspells
The prev links like `/changelog_2021/`
stopped working after 9dc8d1debd
because these files now require specifying the parent `changelog` in the path, like `/changelog/changelog_2021/`.
This fix adds an alias for an old link.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Moving changelog-related docs to a separate dir should make it easier to
navigate in `docs/` folder.
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The change shouldn't have any visual changes or changes to the links.
Signed-off-by: hagen1778 <roman@victoriametrics.com>