[DOC] BACKLOG-1176 -- Document the REST calls for Carte (Kettle Path) (Part 1)

What was done:
1) changed wording according to Chantel's review
Merge pull request #858 from kolinus/BACKLOG-1176-1

[DOC] BACKLOG-1176 -- Document the REST calls for Carte (Kettle Path) (P...
[PDI-13049] - Regression: PDI 5.1 Clone Rows NULLs