Some edits for the new sensor/motor examples (#901)

* Some edits for the new sensor/motor examples

* article typo

* dark and bright

* fix block styling

* I like 'on'

* more block styling

docs/reference/motors/synced/tank.md

@@ -84,7 +84,7 @@ motors.stopAll()
 
 ### Tank tester
 
-This program lets you change the tank values using the brick buttons
+This program lets you change the tank values using the brick buttons.
 
 ```typescript
 let tankB = 0;