Anthony Léonard authored Sep 20, 2016 and Guillaume Roguez committed Sep 21, 2016

A new instance of TelephoneTone was created every time the
sample rate was changed. Consequently, the selected tone
was lost each time it happened and the ALSA backend was
trying to read an empty buffer in an infinite loop when the
contact wasn't answering the call.
The precise changes are :
 * A setSampleRate was added as a method in tonelist[.cpp|.h]
 * A buildTones method was also created to prevent code
   redundancy.
 * setSampleRate is used instead of recreating the object in
   tonecontrol.cpp

Change-Id: I44a86345953068848d0304516d502de5c37bb113
Tuleap: #168


Reviewed-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>