Add ressource folder with profiles

* Profiles:
   * audio ("a_...")
   * video ("v_...")
   * format ("f_...")
Option: reorder setters functions

Symmetry with getters.
Option: fix "is of a specific flag" methods
Option: add getters to current value

Also add private functions to refactore check of FFmpeg return value
(raise exception if error).
GeneratorVideo: refactore creation of rgb pixel
VideoFrame: refactore setParameters