Add 'Background' option for subtitles in VLC for iOS

This very useful feature from OSX version is missing from iOS app. Unfortunately, unless I choose a very ugly colour, subtitles sometimes blend with the video behind them. A semi-transparent box around them is in my opinion genius and I really miss it when' watching videos on iPad.

Thanks for reading, and thank you for making an absolutely groundbreaking player!

added Component::Port: iOS label

assigned to @fkuehne

Thanks a lot for the feedback and the suggestion. VLC for iOS uses a different subtitles renderer compared to the Mac. We are going to re-write it later this year and will definitely take this suggestion into account.

added Difficulty::medium Type::feature labels

changed milestone to %Features paradize

changed milestone to %iOS 2.8

changed milestone to %iOS 3.0

Duplicate of vlc-ios#149

added Status::duplicate label

closed