minor fixes and updates

- signed-off-by: trimstray <trimstray@gmail.com>

Author: trimstray

README.md

@@ -3,8 +3,7 @@
 <br>
 
 <p align="center">
-    <img src="https://github.com/trimstray/the-practical-linux-hardening-guide/blob/master/static/img/main_preview.jpg"
-        alt="Master">
+  <img src="https://github.com/trimstray/the-practical-linux-hardening-guide/blob/master/static/img/main_preview.jpg" alt="Master">
 </p>
 
 <br>
@@ -14,17 +13,11 @@
 <br>
 
 <p align="center">
-  <a href="https://github.com/trimstray/the-practical-linux-hardening-guide/tree/master">
-    <img src="https://img.shields.io/badge/Branch-master-green.svg?longCache=true"
-        alt="Branch">
-  </a>
   <a href="https://github.com/trimstray/the-practical-linux-hardening-guide/pulls">
-    <img src="https://img.shields.io/badge/PRs-welcome-brightgreen.svg?longCache=true"
-        alt="Pull Requests">
+    <img src="https://img.shields.io/badge/PRs-welcome-brightgreen.svg?longCache=true" alt="Pull Requests">
   </a>
   <a href="http://www.gnu.org/licenses/">
-    <img src="https://img.shields.io/badge/License-GNU-blue.svg?longCache=true"
-        alt="License">
+    <img src="https://img.shields.io/badge/License-GNU-blue.svg?longCache=true" alt="License">
   </a>
 </p>