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/Bitwise/BITAND.php

@@ -0,0 +1,54 @@
+<?php
+
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
+
+require __DIR__ . '/../../Header.php';
+
+$category = 'Engineering';
+$functionName = 'BITAND';
+$description = "Returns a bitwise 'AND' of two numbers";
+
+$helper->titles($category, $functionName, $description);
+
+// Create new PhpSpreadsheet object
+$spreadsheet = new Spreadsheet();
+$worksheet = $spreadsheet->getActiveSheet();
+
+// Add some data
+$testData = [
+    [1, 5],
+    [3, 5],
+    [1, 6],
+    [9, 6],
+    [13, 25],
+    [23, 10],
+];
+$testDataCount = count($testData);
+
+$worksheet->fromArray($testData, null, 'A1', true);
+
+for ($row = 1; $row <= $testDataCount; ++$row) {
+    $worksheet->setCellValue('C' . $row, '=TEXT(DEC2BIN(A' . $row . '), "00000")');
+    $worksheet->setCellValue('D' . $row, '=TEXT(DEC2BIN(B' . $row . '), "00000")');
+    $worksheet->setCellValue('E' . $row, '=BITAND(A' . $row . ',B' . $row . ')');
+    $worksheet->setCellValue('F' . $row, '=TEXT(DEC2BIN(E' . $row . '), "00000")');
+}
+
+// Test the formulae
+for ($row = 1; $row <= $testDataCount; ++$row) {
+    $helper->log(
+        "(E$row): Bitwise AND of "
+        . $worksheet->getCell('A' . $row)->getValue()
+        . ' ('
+        . $worksheet->getCell('C' . $row)->getCalculatedValue()
+        . ') and '
+        . $worksheet->getCell('B' . $row)->getValue()
+        . '('
+        . $worksheet->getCell('D' . $row)->getCalculatedValue()
+        . ') is '
+        . $worksheet->getCell('E' . $row)->getCalculatedValue()
+        . ' ('
+        . $worksheet->getCell('F' . $row)->getCalculatedValue()
+        . ')'
+    );
+}