Improved ParameterList interface

Made it easier to handle errors and use default value
ParameterList destructor is no longer virtual

Why should it be ?
Fixed audio build script not defining NAZARA_AUDIO_OPENAL
Fixed ParameterList placement new conflicting with MLT
Added CallOnExit class
Fixed DynLib class not exported
Updated the way module are initialized

It's safer and prevent a bug when initialisation fails
Fixed debug compilation