README.md: Tweak template text

* Let's replace 'Feature 1' with 'Feature-ABC'
  reason: some students kept the 'Feature 1' in the final UG.
* Let's tweak the template for features and usage
  reasons: to fix grammar, to distinguish between output and outcome

docs/README.md

@@ -2,19 +2,28 @@
 
 ## Features 
 
-### Feature 1 
-Description of feature.
+### Feature-ABC
+
+Description of the feature.
+
+### Feature-XYZ
+
+Description of the feature.
 
 ## Usage
 
 ### `Keyword` - Describe action
 
-Describe action and its outcome.
+Describe the action and its outcome.
 
 Example of usage: 
 
 `keyword (optional arguments)`
 
 Expected outcome:
 
-`outcome`
+Description of the outcome.
+
+```
+expected output
+```