* Do not duplicate getters with AudioFrameDesc (getSampleRate,
getChannels...).
* Keep symmetry with VideoCodec (rename getFrameDesc to
getAudioFrameDesc).

Remove comments.

Add OptionArray and OptionMap.

* Easier to manipulate complexe data (in AvTranscoder and in other
libraries...).
* Remove forward declaration of 'Option': need to include 'Context' to
get 'OptionArray' typedef.

* Test NULL pointer to avoid possible crash.
* Do not skip format name with no video track possible.

Remove assert which are already tested before calling init (private)
function.

We delete all the 'StreamTranscoder' in destructor of 'Transcoder':
can't add a reference to a stream from outside like this.

…Index

Symmetry with other processTranscode method.

* An external library could need to update a specific stream during
process.
* Also add a getter to the current Essence in StreamTranscoder, for the
same reason above.

* 2 tests in the python file:
     * Generate a video stream, and set its frame during process.
     * Generate a audio stream, and set its frame during process.
* Swig: add template to have access to DataBuffer methods in bindings.
* IInputEssence: add virtual method setFrame. Reasons:
     * avoid cast when setFrame.
     * can access this feature whithout issue in bindings.
     * it could be a case to set some frames of a stream which is from
an input file (still not implemented).

* The functions returns duration of last packet added.
* Not what we expected, and not used.

* The method setOutputFps does not do what the user expected: the fps of
Transcoder is only used for progress bar (no consequencies in transcode
process !).
* This kind of method must be implemented in the outputStream on which
we want to update the fps.

This private function decodes the next frame (call
avcodec_decode_audio4).

* Return false as status of decoding if size of frame is 0.

Symmetry with AvInputAudio: add private function decodeNextFrame.

Get Video / Audio FrameDesc from a frameDesc instead of a link to a
codec.

Skip the first one which was an undefined codec in the enum list.

* Manage memory of StreamTranscoder by spliting streams into 2 vectors.
* Add pyTest "testTranscoderAdd" to test if we correctly manage memory.

Get only one instruction "new".

Use make_pair.

…into dev_setFrame_v2

Conflicts:
	src/AvTranscoder/transcoder/Transcoder.cpp
	src/AvTranscoder/transcoder/Transcoder.hpp
Fix pyTest testSetFrame.