Improved VictoriaMetrics documentation for cloud
Related issue: https://github.com/VictoriaMetrics/cloud/issues/2143
### Describe Your Changes
Please provide a brief description of the changes you made. Be as
specific as possible to help others understand the purpose and impact of
your modifications.
### Checklist
The following checks are **mandatory**:
- [x] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
(cherry picked from commit 4c228f1e18)
### Describe Your Changes
* `sort` param is unused by the current website engine, and was present only for compatibility
with previous website engine. It is time to remove it as it makes no effect
* re-structure guides content into folders to simplify assets management
### Checklist
The following checks are **mandatory**:
- [ ] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
(cherry picked from commit 35d77a3bed)
### Describe Your Changes
These changes were made as part of the title transition from Managed
VictoriaMetrics to VictoriaMetrics Cloud
### Checklist
The following checks are **mandatory**:
- [x] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
(cherry picked from commit d09182da11)
