Syntax highlighting for Bash in README

Author: simonw

{{cookiecutter.hyphenated}}/README.md

@@ -10,25 +10,26 @@
 ## Installation
 
 Install this library using `pip`:
-
-    pip install {{ cookiecutter.hyphenated }}
-
+```bash
+pip install {{ cookiecutter.hyphenated }}
+```
 ## Usage
 
 Usage instructions go here.
 
 ## Development
 
 To contribute to this library, first checkout the code. Then create a new virtual environment:
-
-    cd {{ cookiecutter.hyphenated }}
-    python -m venv venv
-    source venv/bin/activate
-
+```bash
+cd {{ cookiecutter.hyphenated }}
+python -m venv venv
+source venv/bin/activate
+```
 Now install the dependencies and test dependencies:
-
-    pip install -e '.[test]'
-
+```bash
+pip install -e '.[test]'
+```
 To run the tests:
-
-    pytest
+```bash
+pytest
+```