Use mb_convert_encoding when encoding detected, else try utf8_encode

[stefandoorn]

Basically I was getting an error sometimes:

mb_convert_encoding(): Illegal character encoding specified

It happened that the mb_detect_encoding call was returning FALSE in some cases, which in turn let mb_convert_encoding raise an error.

Small adjustment made to only use mb_convert_encoding in case there is a encoding known. The SimpleXmlElement object creation was not working in the same case when it was not converted to UTF-8, therefor the utf8_encode call is introduced. I'm only performing both in the situation mb_convert_encoding is available, as we only did transform things when this function exists. I can't test it very well what would happen in the case it ain't available.

@gabrielbull I think this is safe to do (and works better in my set-up), but could you also have a look?

[gabrielbull]

That looks safe to me, good job on maintaining the project! 🌟