[bluray] Some fixes/improvements of bluray nav mode.

edd8ad6 and  d06719c prevent (or try to at least) a infinite loop in CDVDInputStreamBluray::Read if the next title can not be played/read by libbluray 0.4.0 in nav mode, e.g., because the next title is a bd-j title.
As a side note: In version 0.5.0 the function returns -1 in this case.

@elupus Could you please have a look?