Moved basics chapters into sub-folder and reformatted config file

chapters/basics/classes-constructor.md

@@ -0,0 +1,60 @@
+Whenever you create an object in PHP, you put parentheses after the class name.
+In the previous examples, we always left the parentheses empty.
+```php
+<?php
+
+class Hat
+{
+    public $color;
+
+    public function setColor($color)
+    {
+        $this->color = $color;
+    }
+}
+
+$hat = new Hat();
+```
+
+However, you can actually pass data into the parentheses like a function.
+The data will be passed to a special function on the class called a constructor.
+```php
+class Ballcap
+{
+    public $color;
+
+    public function __construct($color)
+    {
+        $this->color = $color;
+    }
+}
+```
+
+A constructor is not required, but can make creating a new object easier.
+They are usually used to define the initial value of a property.
+Instead of writing:
+```php
+$hat = new Hat();
+$hat->setColor('Red');
+```
+
+You can write:
+```php
+$ballcap = new Ballcap('Blue');
+```
+
+Constructors do not return values because the return value is always a new object.
+```php
+class Tophat
+{
+    public function __construct($color)
+    {
+        return $color;
+    }
+}
+```
+
+`$tophat` now holds an instance of `Tophat`, not the string "Grey".
+```php
+$tophat = new Tophat('Grey');
+```