Move Exceptions in a separate directory + Fixed Range function

Signed-off-by: davidarendsen <davidarendsen@hey.com>

src/Functions/Base.php

@@ -3,6 +3,7 @@
 namespace Arendsen\FluxQueryBuilder\Functions;
 
 use Arendsen\FluxQueryBuilder\Formatters;
+use Arendsen\FluxQueryBuilder\Function\FunctionNotImplementedException;
 
 abstract class Base {
 

src/Functions/FunctionNotImplementedException.php

@@ -1,7 +0,0 @@
-<?php
-
-namespace Arendsen\FluxQueryBuilder\Functions;
-
-use Exception;
-
-class FunctionNotImplementedException extends Exception {}

src/Functions/Range.php

@@ -2,7 +2,7 @@
 
 namespace Arendsen\FluxQueryBuilder\Functions;
 
-use Arendsen\FluxQueryBuilder\Formatters;
+use Arendsen\FluxQueryBuilder\Exception\FunctionRequiredSettingMissingException;
 
 class Range extends Base {
 
@@ -18,7 +18,18 @@ class Range extends Base {
 
     public function __toString()
     {
-        return '|> range(' . Formatters::toFluxArrayString($this->settings) . ') ';
+        if(!isset($this->settings['start']))
+        {
+            throw new FunctionRequiredSettingMissingException('Range', 'Start setting is required!');
+        }
+
+        $settingsString = 'start: ' . $this->settings['start'];
+        if(isset($this->settings['stop']))
+        {
+            $settingsString .= ', stop: ' . $this->settings['stop'];
+        }
+
+        return '|> range(' . $settingsString . ') ';
     }
 
 }