readme.md edit

README.md

@@ -4,7 +4,7 @@
  - Daily AWS consumption reporter w/ slack
 
 # installation
-```
+```bash
 $ python3 -m venv --clear venv
 $ source ./venv/bin/activate 
 $ pip install -r requirements.txt
@@ -14,12 +14,12 @@ $ pip install -r requirements.txt
 
  - settings file -> see `bill_man.json.example`
  - run
-    ```
+```bash
 $ source ./venv/bin/activate 
 $ python bill_man.py start
 ```
  - stop
-    ```
+```bash
 $ source ./venv/bin/activate 
 $ python bill_man.py stop
 ```