Fixes ddiakopoulos/libnyquist#42

[phniix]

This aids in rethrowing exceptions from callers wanting to:

• void NyquistIO::Load(AudioData * data, const std::vector & buffer)
• void NyquistIO::Load(AudioData * data, const std::string & extension, const std::vector & buffer)

where std::exceptions are not raised by the catch on: https://github.com/phniix/libnyquist/blob/97d71768ef1fda423368bed87c090afbcfd1df81/src/Common.cpp#L135

-- Please consider these solutions to be inline with f94005c39885d2b66b5f579232b4d6d295636a66 I'm less fussed about the wording that gets sent to std::cerr. There are a number of failures from the decoder being propagated to the caller, that might be very helpful to be sent up, rather than swallowed up.

[ddiakopoulos]

Looks good to me. Thanks for your contribution!

[phniix]

Thank you!