Fix deprecated code.

* Remove Vec::get for indexing in favor of vec[T],
* Use string::raw::from_buf instead of str::raw::from_c_str.
Merge pull request #9 from bfabio/deprecated

Fix deprecated code.
Don't crash if SDL AudioDevice fails to open
Merge pull request #10 from xmasotto/master

Don't crash if SDL AudioDevice fails to open
Use where clauses