Fix : 9784 Added the note for display.max_colwidth in dsintro.rst
- [x] closes #9784
- [ ] tests added / passed
- [ ] passes `git diff upstream/master | flake8 --diff`
- [ ] whatsnew entry

ok sir, i will add an example with Long names or strings that will make it more clear. 
 sir, any reviews
 filename changed to generic
 thanks!
