java.nio.Bits is currently initialized when setting up the System.in/out PrintStreams in System.initPhase1, but it doesn't have to be:

- Bits.unsafe() can be replaced by direct use of Unsafe.getUnsafe();
- Bits.byteOrder() can be removed, and the read of platform native ByteOrder moved to... ByteOrder

This brings a small reduction of class loading during System.initPhase1 (-4 classes)