Transcoder: clean add functions

* Update verbose: upper case when start new sentences.
* Throw exception if invalid operation (instead of print something in
verbose on just return without doing nothing).
* Add comments.
StreamTranscoder: remove processRewrap( subStreamIndex )

* Can't demultiplexing and re-wrap a stream.
ProfileLoader: clean update

* Check if 'avProfileIdentificator' key exist in map.
* Do nothing if profile already exists.
Transcoder: transcode stream if user wants to demultiplexing and copy a stream

* Same behavior as ffmpeg: transcode with the same "profile" as input.
* Need to update 'sampleFormat' of AudioStreamProperty: use
av_get_sample_fmt_name (ffmpeg function insted of creating our specific
strings).
Transcoder: refactore case when getting profile from input file
pyTest: fix audioStream property sampleFormat

Because now we get string which correspond to sampleFormat from
av_get_sample_fmt_name (ffmpeg function).
AudioProperties: add sampleFormatName and sampleFormatLongName

* Keep in the stucture the sample format name from FFmpeg
(sampleFormatName), and the more user friendly name
(sampleFormatLongName).
* Update pyTest consequently.
Merge pull request #126 from cchampet/dev_demux_rewrap

Manage "rewrap" of stream in case of demultiplexing
log: improve warning messages

For the next classes:
    * AvInputVideo
    * AvOutputVideo
    * AvOutputAudio
    * InputFile
    * OutputFile
Merge pull request #128 from cchampet/fix_log

log: improve warning messages