Updates to 3rd party libraries

Add Dockerfile and specific docker-php.ini

inc/vendor/markbaker/complex/classes/src/functions/atan.php

@@ -0,0 +1,45 @@
+<?php
+
+/**
+ *
+ * Function code for the complex atan() function
+ *
+ * @copyright  Copyright (c) 2013-2018 Mark Baker (https://github.com/MarkBaker/PHPComplex)
+ * @license    https://opensource.org/licenses/MIT    MIT
+ */
+namespace Complex;
+
+//include_once 'Math/Complex.php';
+//include_once 'Math/ComplexOp.php';
+
+/**
+ * Returns the inverse tangent of a complex number.
+ *
+ * @param     Complex|mixed    $complex    Complex number or a numeric value.
+ * @return    Complex          The inverse tangent of the complex argument.
+ * @throws    Exception        If argument isn't a valid real or complex number.
+ * @throws    \InvalidArgumentException    If function would result in a division by zero
+ */
+function atan($complex)
+{
+    $complex = Complex::validateComplexArgument($complex);
+
+    if ($complex->isReal()) {
+        return new Complex(\atan($complex->getReal()));
+    }
+
+    $t1Value = new Complex(-1 * $complex->getImaginary(), $complex->getReal());
+    $uValue = new Complex(1, 0);
+
+    $d1Value = clone $uValue;
+    $d1Value = subtract($d1Value, $t1Value);
+    $d2Value = add($t1Value, $uValue);
+    $uResult = $d1Value->divideBy($d2Value);
+    $uResult = ln($uResult);
+
+    return new Complex(
+        (($uResult->getImaginary() == M_PI) ? -M_PI : $uResult->getImaginary()) * -0.5,
+        $uResult->getReal() * 0.5,
+        $complex->getSuffix()
+    );
+}