[MINOR][DOC] Fix the descriptions for `properties` argument in the documenation for jdbc APIs

## What changes were proposed in this pull request?

This should be credited to mvervuurt. The main purpose of this PR is
 - simply to include the change for the same instance in `DataFrameReader` just to match up.
 - just avoid duplicately verifying the PR (as I already did).

The documentation for both should be the same because both assume the `properties` should be  the same `dict` for the same option.

## How was this patch tested?

Manually building Python documentation.

This will produce the output as below:

- `DataFrameReader`

![2016-08-17 11 12 00](https://cloud.githubusercontent.com/assets/6477701/17722764/b3f6568e-646f-11e6-8b75-4fb672f3f366.png)

- `DataFrameWriter`

![2016-08-17 11 12 10](https://cloud.githubusercontent.com/assets/6477701/17722765/b58cb308-646f-11e6-841a-32f19800d139.png)

Closes #14624

Author: hyukjinkwon <gurwls223@gmail.com>
Author: mvervuurt <m.a.vervuurt@gmail.com>

Closes #14677 from HyukjinKwon/typo-python.

python/pyspark/sql/readwriter.py

@@ -401,8 +401,9 @@ class DataFrameReader(OptionUtils):
         :param numPartitions: the number of partitions
         :param predicates: a list of expressions suitable for inclusion in WHERE clauses;
                            each one defines one partition of the :class:`DataFrame`
-        :param properties: a dictionary of JDBC database connection arguments; normally,
-                           at least a "user" and "password" property should be included
+        :param properties: a dictionary of JDBC database connection arguments. Normally at
+                           least properties "user" and "password" with their corresponding values.
+                           For example { 'user' : 'SYSTEM', 'password' : 'mypassword' }
         :return: a DataFrame
         """
         if properties is None:
@@ -716,9 +717,9 @@ class DataFrameWriter(OptionUtils):
             * ``overwrite``: Overwrite existing data.
             * ``ignore``: Silently ignore this operation if data already exists.
             * ``error`` (default case): Throw an exception if data already exists.
-        :param properties: JDBC database connection arguments, a list of
-                           arbitrary string tag/value. Normally at least a
-                           "user" and "password" property should be included.
+        :param properties: a dictionary of JDBC database connection arguments. Normally at
+                           least properties "user" and "password" with their corresponding values.
+                           For example { 'user' : 'SYSTEM', 'password' : 'mypassword' }
         """
         if properties is None:
             properties = dict()