add tokenization image

Author: zaidalyafeai

README.md

@@ -26,6 +26,10 @@ tokenizer.process_data('samples/data.txt', clean = True, segment = True, normali
 ```
 
 ### Tokenization
+<p align="center"> 
+ <img src = "logo_tokenizers.png" width = "200px"/>
+ </p>
+
 ```python
 import tkseem as tk
 tokenizer = tk.WordTokenizer()