Number/int fix; start level

As I mentioned, this will make start level to be chosen beforehand.
Hope it helps and don't destroy anything! :o

Best regards,
Leandro
I've set "_manual_level" only if "HLSSettings.startFromLevel" wasn't auto, because once in **manual** mode, "_hls.autolevel" would return **"true"** at manifest load time.

I can workaround it in my code, but do you have any suggestion or just cut it out to proceed with PR?