Add addPage() operation in TemplateProcessor

[YvesAmmann]

Added new method addPage() and replace & to & in method setValue().

Description

Create a bulk letter with the same template for each page.

$word = new \PhpOffice\PhpWord\PhpWord();
$document = $word->loadTemplate('Template.docx');

$page = 0;

foreach ($document_page as $document_address) {
	if ($page > 0) {
		$document->addPage();
	}

	$document->setValue('ADDRESS', $document_address);
}

$document->saveAs('Bulkletter.docx');

Checklist:

• I have run composer run-script check --timeout=0 and no errors were reported
• The new code is covered by unit tests (check build/coverage for coverage report)
• I have update the documentation to describe the changes

[troosan]

@YvesAmmann instead of replacing & info & you should call

Settings::setOutputEscapingEnabled(true);

If I'm not mistaken this should make sure entities are escaped.