More problem formatting fixes

Author: Alan Shaw

exercises/blink_blink/problem.md

@@ -55,6 +55,7 @@ In all of your solutions you will need to:
 ```
 
 ## Components
+
 - LED - http://node-ardx.org/electronics-primer#led
 
 > Emits light when a small current is passed through it (only in one direction).

exercises/fire_alarm/problem.md

@@ -46,4 +46,6 @@ Pin 5   o----------------------         |
 - LED - https://github.com/rwaldron/johnny-five/wiki/Led
 - Piezo - https://github.com/rwaldron/johnny-five/blob/master/docs/piezo.md
 - TMP36 - https://github.com/rwaldron/johnny-five/blob/master/docs/sensor-temperature-tmp36.md
-- Button - https://github.com/rwaldron/johnny-five/wiki/Button#usage
+- Button - https://github.com/rwaldron/johnny-five/wiki/Button#usage
+
+---

exercises/robot_arm/problem.md

@@ -32,6 +32,7 @@ GND  o---.------/\/\/------.
 ```
 
 ## Components
+
 - Potentiometer - http://node-ardx.org/electronics-primer#pot
 
 > Produces a variable resistance dependant on the angular position of the shaft.
@@ -42,6 +43,7 @@ GND  o---.------/\/\/------.
 - Fn - https://github.com/rwaldron/johnny-five/blob/master/lib/fn.js
 
 ## Hints
+
 - A potentiometer is another use case for the Sensor object...
 - A pot produces input values between 0 and 1023.
 - A servo can typically be moved between 0 and 179 degrees.

exercises/servo_wave/problem.md

@@ -7,6 +7,7 @@ __Make a servo wave at you for 3 seconds, stop, and return to center.__
 - Check the docs to see how to bring it back into line
 
 ## Boilerplate
+
 ```js
   var five = require('johnny-five')
   var board = new five.Board()
@@ -36,11 +37,13 @@ GND  o--. | .--o  Pin 9
 ```
 
 ## Components
+
 - Servo - http://node-ardx.org/electronics-primer#servo
 
 > Takes a timed pulse and converts it into an angular position of the output shaft.
 
 ## Docs
+
 - Servo - https://github.com/rwaldron/johnny-five/wiki/Servo#api
 - Board - https://github.com/rwaldron/johnny-five/wiki/Board#api
 

exercises/street_lamp/problem.md

@@ -17,14 +17,17 @@ __Build a street lamp that turns on as it gets dark.__
 ```
 
 ## Components
+
 - Photoresistor - http://node-ardx.org/electronics-primer#photoresistor
 
 > Produces a variable resistance dependant on the amount of incident light.
 
 ## Docs
+
 - Sensor - https://github.com/rwaldron/johnny-five/wiki/Sensor
 
 ## Hints
+
 `johnny-five` has a generic Sensor object for handling various analog inputs.
 It fires a data event with the current reading of the sensor.
 The sensor value is available to the callback as `this.value`