"Missing @property annotations" inspection improvements

[Brandon Kelly]

Before I get into the actual FR, some definitions:

• Getter: A getX() method on a class that extends yii\base\BaseObject, without any required arguments, which yii\base\BaseObject::__get() will call when $obj->x is accessed.

  // valid:
  public function getAuthor()
  public function getAuthor($arg = 'default')
  
  // invalid:
  public function getauthor() // lowercase 'a'
  public function getAuthor($arg) // $arg is required

• Setter: A setX() method on a class that extends yii\base\BaseObject, with one required argument (the first one), which yii\base\BaseObject::__set() will call when $obj->x is set to something.

  // valid:
  public function setAuthor($arg)
  public function setAuthor($arg1, $arg2 = 'default')
  
  // invalid:
  public function setauthor() // lowercase 'a'
  public function setAuthor() // no required argument
  public function setAuthor($arg1, $arg2) // $arg2 is required

If a getter exists but no corresponding setter, the "Missing @Property annotations" inspection should create a @property-read tag instead of @property.

If a setter exists but no corresponding getter, then a @property-write tag should be created instead of @property.

If both exist, then continue to create a @property tag.