update README.md

Author: ahmnouira

README.md

@@ -1,11 +1,11 @@
 # chat-app 
 
-:a: real-time chat ionic application with firebase.
+**:a: real-time chat ionic application with firebase**.
 
 Our chat application will show a login page withe _e-mail_ and _password_ fields. The user will be able to log in or create a new account, when a user logs in, it will go to a tabs interface where we have a list of all users of the application, 
 
 ## Overview 
 
-[register](/img/register.png)
+![register](/img/register.png)
 
-[login](/img/login.png)
+![login](/img/login.png)