This includes a leading trimming node to act as a test.

This is hopefully a temporary measure to address a bug in the lock-free
algorithm.

Fixed compiling for iOS 11.x and earlier

Public issue https://github.com/mackron/miniaudio/issues/363

It looks like IOID will be null when both modes are supported.

Public issue https://github.com/mackron/miniaudio/issues/365

Fix use of uninitialized variables

Fixed compilation warnings & errors on iOS

This applies for resource manager data source and sounds.

This addresses an issue where data streams can have a delay between
loop points due to it's asynchronous loading mechanism. With this
change, streams should now have a clean loop transition.