Require FileOutputProxy for python bindings
Require FileOutputProxy for python bindings

Throw configuration error for python bindings in the case if
FileOutputProxy algorith was excluded (#553).

MTG/essentia,carthach/essentia,carthach/essentia,carthach/essentia,MTG/essentia,MTG/essentia,carthach/essentia,MTG/essentia,MTG/essentia,carthach/essentia