[BUG] _cat help content cleanup after fork

[lukas-vlcek]

Describe the bug

It seems that help output of the _cat API was not fully reviewed when the fork happened.

One example: http://localhost:9200/_cat/nodes?help

id                                 | id,nodeId                                   | unique node id                                                                                                   
pid                                | p                                           | process id                                                                                                       
ip                                 | i                                           | ip address                                                                                                       
port                               | po                                          | bound transport port                                                                                             
http_address                       | http                                        | bound http address                                                                                               
version                            | v                                           | es version                                                                                                       
type                               | t                                           | es distribution type                                                                                             
build                              | b                                           | es build hash  
[... cont.]

See the explanation for version, type and build.

It would be useful to review all _cat API help texts.

Related component

Other

To Reproduce

1. Go to http://localhost:9200/_cat/
2. Iterate over all options (ie. allocation, segment_replication, ...)
3. Append ?help to the URL
4. Check the help text, especially the explanation column

Expected behavior

Help output should not refer to previous product name or acronyms.

Additional Details

No response

[lukas-vlcek]

IMO this is an ideal candidate for the "good first issue" category.