Provide a separator for cloned blocks

[thomasb88]

Is your feature request related to a problem? Please describe.

When cloning blocks using cloneBlock function in TemplateProcessor.php, add a parameter to separate the created blocks
(like page break, line break...)

Describe the solution you'd like

Replace

if ($replace) {
$this->tempDocumentMainPart = str_replace(
$matches[2] . $matches[3] . $matches[4],
implode('', $cloned),
$this->tempDocumentMainPart
);
}

by

if ($replace) {
$this->tempDocumentMainPart = str_replace(
$matches[2] . $matches[3] . $matches[4],
implode($xml_separator, $cloned),
$this->tempDocumentMainPart
);
}

Where $xml_separator is built from a parameter, like (old school xml building)

switch($separator){
case "pagebreak":
$xml_separator = $this->xml_pagebreak('page');
break;
case "linebreak":
$xml_separator = $this->xml_linebreak();
break;
default:
$xml_separator = '';
break;
}

Describe alternatives you've considered

Add it directly in the template, but if added at the end of the template, then the last one is not wanted, or if added at the beginning, then the first one is not wanted.

Additional context