Add missing code-language flag

README.md

@@ -4,7 +4,7 @@
 Ruby on Rails application serving as backend for turnie.re
 
 # Installation
-```
+```bash
 # install dependencies
 $ bundle install
 # run migrations
@@ -13,11 +13,11 @@ $ rails db:migrate
 
 # Running
 Development (without mail confirmation and separate database):
-```
+```bash
 $ RAILS_ENV=development rails server
 ```
 
 # Generate diagrams
-```
-rails diagram:all_with_engines
+```bash
+$ rails diagram:all_with_engines
 ```