line breaks look nicer

README.md

@@ -50,22 +50,27 @@ This is a large corpus of 41,578 preprocessed sms spam messages and emails sent
 
 <br>
 
-## Some preprcoessing algorithms
+### Some preprcoessing algorithms
 - [spam_assassin.js](./spam_assassin.js), followed by [spam_assassin.py](./spam_assassin.py)
 - [enron_spam.py](./enron_spam.py)
 
+<br>
 
-## Data composition
+### Data composition
 ![](./spam_counts.png)
 
-## Description
+<br>
+
+### Description
 To make the text format between sms messages and emails consistent, email subjects and content are separated by two newlines:
 
 ```python
 text = email.subject + "\n\n" + email.content
 ```
 
-## Original source
+<br>
+
+### Original source
 - https://huggingface.co/datasets/sms_spam
 - https://github.com/MWiechmann/enron_spam_data
 - https://github.com/stdlib-js/datasets-spam-assassin