diff() is a manipulation function, not a display function

[Bilge]

Describe the bug
In the docs, documentation for diff() is found under the difference topic, filed under the top-level heading, display. However, diffing is not concerned with the display of dates but of manipulating them, ergo it is misclassified.

Expected behavior
Difference topic should be filed under manipulation heading.

Information
n/a

[iamkun]

this manipulating section stores methods that could make a change to date time, while displaying is to display date-times in some way. And diff just tell you the difference between date-times rather than change them.