Reorganize Samples

The samples have become unwieldy when running them from a browser. In particular, the drop-down lists are fixed size with no scrolling, and many of them are now just too large. I have moved all the Calculation samples up a level, and broken several categories (Basic, Chart, DateTime, Engineering, Financial, and Reader) into several pieces.

Convert-Online (now found in the Engineering category) had a number of different problems which are now resolved. It is the only member with any significant code change.

samples/ComplexNumbers2/IMDIV.php

@@ -0,0 +1,43 @@
+<?php
+
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
+
+require __DIR__ . '/../../Header.php';
+
+$category = 'Engineering';
+$functionName = 'IMDIV';
+$description = 'Returns the quotient of two complex numbers in x + yi or x + yj text format';
+
+$helper->titles($category, $functionName, $description);
+
+// Create new PhpSpreadsheet object
+$spreadsheet = new Spreadsheet();
+$worksheet = $spreadsheet->getActiveSheet();
+
+// Add some data
+$testData = [
+    ['3+4i', '5-3i'],
+    ['3+4i', '5+3i'],
+    ['-238+240i', '10+24i'],
+    ['1+2i', 30],
+    ['1+2i', '2i'],
+];
+$testDataCount = count($testData);
+
+$worksheet->fromArray($testData, null, 'A1', true);
+
+for ($row = 1; $row <= $testDataCount; ++$row) {
+    $worksheet->setCellValue('C' . $row, '=IMDIV(A' . $row . ', B' . $row . ')');
+}
+
+// Test the formulae
+for ($row = 1; $row <= $testDataCount; ++$row) {
+    $helper->log(
+        "(E$row): The Quotient of "
+        . $worksheet->getCell('A' . $row)->getValue()
+        . ' and '
+        . $worksheet->getCell('B' . $row)->getValue()
+        . ' is '
+        . $worksheet->getCell('C' . $row)->getCalculatedValue()
+    );
+}