Remove subsection for Databricks Runtime in Getting Started (#964)

![Screen Shot 2019-10-29 at 10 36 12 AM](https://user-images.githubusercontent.com/6477701/67730295-f4e05a80-fa37-11e9-8da0-2c974f6a5f07.png)

Author: HyukjinKwon

README.md

@@ -35,12 +35,23 @@ Try the Koalas 10 minutes tutorial on a live Jupyter notebook [here](https://myb
 
 ## Getting Started
 
-The recommended way of installing Koalas is Conda. You can use not only Conda but also multiple ways to install Koalas. See [Installation](https://koalas.readthedocs.io/en/latest/getting_started/install.html) for full instructions to install Koalas.
+The recommended way of installing Koalas is Conda as below.
 
 ```bash
 conda install koalas -c conda-forge
 ```
 
+You can use not only Conda but also multiple ways to install Koalas. See [Installation](https://koalas.readthedocs.io/en/latest/getting_started/install.html) for full instructions to install Koalas.
+
+If you are a Databricks Runtime user, you can install Koalas using the Libraries tab on the cluster UI, or using `dbutils` in a notebook as below, for the regular Databricks Runtime.
+
+```python
+dbutils.library.installPyPI("koalas")
+dbutils.library.restartPython()
+```
+
+Note that Koalas requires Databricks Runtime 5.x or above. In the future, we will package Koalas out-of-the-box in both the regular Databricks Runtime and Databricks Runtime for Machine Learning.
+
 Now you can turn a pandas DataFrame into a Koalas DataFrame that is API-compliant with the former:
 
 ```python
@@ -61,17 +72,6 @@ df['x2'] = df.x * df.x
 
 For more details, see [Getting Started](https://koalas.readthedocs.io/en/latest/getting_started/index.html) and [Dependencies](https://koalas.readthedocs.io/en/latest/getting_started/install.html#dependencies) in the official documentation.
 
-### Databricks Runtime
-
-Koalas requires Databricks Runtime 5.x or above. For the regular Databricks Runtime, you can install Koalas using the Libraries tab on the cluster UI, or using dbutils in a notebook:
-
-```python
-dbutils.library.installPyPI("koalas")
-dbutils.library.restartPython()
-```
-
-In the future, we will package Koalas out-of-the-box in both the regular Databricks Runtime and Databricks Runtime for Machine Learning.
-
 
 ## Contributing Guide