Check the encoding against the list of supported encodings before ever calling `mb_convert_encoding()`.

Co-authored-by: jrfnl <[email protected]>

... including the upcoming PHP 8.0 (nightly).

Co-authored-by: jrfnl <[email protected]>

Any function call to the `get_magic_quotes_gpc()` method now needs to be wrapped in a `function_exists()`.

Co-authored-by: jrfnl <[email protected]>

PHP 7.4 deprecated curly brace array access, PHP 8.0 has removed support for it completely.

This fixes the instances of this syntax in SimplePie.

Co-authored-by: jrfnl <[email protected]>

…ameters (#656)

By giving the `&$working` parameter a default value, this issue is circumvented.

Co-authored-by: jrfnl <[email protected]>

Using cURL CURLOPT_FOLLOWLOCATION instead of the manual method in
SimplePie hides the list of HTTP redirects along the way, and prevents
the distinction of e.g. 301 vs. 302 redirects needed for
`simplepie->subscribe_url(true)`.

This patch disables CURLOPT_FOLLOWLOCATION in SimplePie, and fixes the
manual method at the same time (curl_options where not given to
following redirection requests).
The use of CURLOPT_FOLLOWLOCATION was nevertheless not systematic (only
when open_basedir was not set), so now there is only one logic
independent of open_basedir.

* Updated to version 1.5.6