DOC: update the pandas.date_range() docstring
Checklist for the pandas documentation sprint (ignore this if you are doing
an unrelated PR):

- [x] PR title is "DOC: update the <your-function-or-method> docstring"
- [x] The validation script passes: `scripts/validate_docstrings.py <your-function-or-method>`
- [x] The PEP8 style check passes: `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] The html version looks good: `python doc/make.py --single <your-function-or-method>`
- [x] It has been proofread on language by another sprint participant

Please include the output of the validation script below between the "```" ticks:

```
Errors found:
	Errors in parameters section
		Parameters {'kwargs'} not documented
```

If the validation script still gives errors, but you think there is a good reason
to deviate in this case (and there are certainly such cases), please state this
explicitly.


Checklist for other PRs (remove this part if you are doing a PR for the pandas documentation sprint):

- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Can you insert the output of scripts/validate_docstrings.py?  Just did.

`See Also` section is not being detected and I asked on the Gitter to @TomAugspurger , he said ignore kwargs Looks like the validation fails?
Errors found:
	Errors in parameters section
		Parameters {'kwargs'} not documented
	See Also section not found Just a couple small comments. Can ignore the kwargs issue. @TomAugspurger : Please check changes now. I've made the changes as you suggested Have made all the required changes as per reviewers feedback. Can be merged now! @nipunbatra I pushed a commit with some whitespace normalization so that the doctests would pass. @TomAugspurger I think you pinged the wrong Nipun :D 
Pinging https://github.com/nipunsadvilkar 😬 sorry! @TomAugspurger : Thanks! Do I need to make any other changes? Nope, we're good thanks!