DOC: Updated the docstring of pandas.Series.str.get
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:

```
################################################################################
###################### Docstring (pandas.Series.str.get)  ######################
################################################################################

Extract element for each component.

Extract element from lists, tuples, or strings in each element in the
Series/Index.

Parameters
----------
i : int
    Integer index (location).

Returns
-------
items : Series/Index of objects

Examples
--------
>>> x = pd.Series(["String", (1, 2, 4), ["a", "b", "c"]])
>>> x
0       String
1    (1, 2, 4)
2    [a, b, c]
dtype: object

>>> x.str.get(1)
0      t
1      2
2      b
dtype: object

################################################################################
################################## Validation ##################################
################################################################################

Errors found:
	See Also section not found
```