The audio_file classes (wav, ogg, opus) represent audio files.

- audio_file is an abstract base class that holds the audio data and info.

- each derived class loads the data in its constructor.

- currently the old code is used for the loading.
Audio file factory

The audio_file_factory class has one static method that returns a
std::unique_ptr<audio> that points to a wav_file, ogg_file or
opus file depending on the extension of the provided filename.
Changed the name of bit_depth to byte_depth

The name was changed because bit_depth was inaccurate.
The value is the actual bytes.
Audio file returns const pointer

Changed the void pointer that is returned by audio_file.get_audio_data()
to const void.
Remove MusicSound

Since the file system does not support partially loading a file
MusicSound does not have any uses. Its functionality is now
part of LoopingSound.
Remove the audio_file hierarchy

Removed the audio_file (and {wav,ogg,opus}_file} in favor of a simpler
AudioData struct, which contains the relevant audio data. Reduce the
audio_file_factory to functions that return AudioData objects.
Update CMakeLists.txt
AudioData now deletes any memory it owns.

If rawSamples* is owned by an AudioData object, it will be deleted
during destruction, this is the case for loaded audio files.

Also, a few ugly casts were removed.
Found a typo
Detect whether Python2 exists when building NaCl game modules and set PNACLPYTHON before executing NaCl build cmds
Ignore NaCl binaries.
Initial work on implementing the filesystem in the vm
Add comparison operator to AudioData
Fix typo
Change all #ifdefs to use the new BUILD_* target macros
Move the filesystem compatibility wrapper to qcommon
Implement the new wav loader.

WavCodec uses engine/framework/Filesystem to read the audio files.

All the relevant data is returned in a AudioData struct.

In case of an error an empty AudioData is returned.
Fix Resource::Prune segfaulting
Improve deps package generation, resolve symlinks on windows platforms
Use zip for deps on windows