PHP 7 8 + Major Updates

[tablatronix]

Ill make a PR but tracking for php deprecation warnings or major ver breaking changes to be fixed.

[tablatronix]

#1246
#1223
#1269
#1343

[BurninLeo]

There is this line in changedata.php (twice)

if (isset($i18n['TRANSLITERATION']) && is_array($translit=$i18n['TRANSLITERATION']) && count($translit>0)) {

The count($translit>0) is probably meant to be (count($translit)>0) or better !empty($translit) - PHP 8.1 stopped processing there for me.

[BurninLeo]

This function in admin/inc/basic.php breaks edits in PHP 8.1, because there is no more get_magic_quotes_gpc()

function safe_slash_html($text) {
	if (get_magic_quotes_gpc()==0) {
		$text = addslashes(htmlspecialchars($text, ENT_QUOTES, 'UTF-8'));
	} else {
		$text = htmlspecialchars($text, ENT_QUOTES, 'UTF-8');
	}
	return xmlFilterChars($text);
}