adding speech activity detection
small bug fix
Improvements to the speech activity detection model.

The analyser outputs 2 new estimates
* frame-level estimate corresponding to the raw speech/non speech estimate, filtered with dilatation and erosion procedures, remove some outliers
* speech-non speech segments, inferred from the dilatation erosion/procedure

The analyser can be initialised with 3 new options:
* size of the window used for the dilatation and erosion procedures
* threshold for the decision of speech VS non speech
* bounds for the raw estimates (usefull for plotting)
code cleaning
Merge remote-tracking branch 'upstream/diadems' into diadems

Conflicts:
	timeside/analyzer/limsi_diarization.py
	timeside/analyzer/limsi_sad.py
small modifs related with the new analyser interface
models moved by parisson somewhere else
Merge pull request #59 from DavidDoukhan/diadems

SV bugfix, improvements of the speech activity detection, cleanup