docs: Get mkdocs working

tests/basic.spt

@@ -35,14 +35,14 @@ cloning this fostr project. Then, either:
    
 For example, this snippet generates the following Python:
 ```python
-{! ../examples/emit_sum.py extract:
+{! ../tests/emit_sum.py extract:
   start: 'Stdio\s='
 !}
 ```
 (which writes "192" to standard output), or this non-idiomatic, inefficient, but
 working Javascript:
 ```javascript
-{! ../examples/emit_sum.js extract:
+{! ../tests/emit_sum.js extract:
   start: '^}'
 !}
 ```