Update Sox Reverb effect for parameter changes but do not install reverb

Update Sox Reverb effect for parameter changes but do not install reverb
and pitch shift because they do not work. Sox man page says reverb adds
a delay and increases the length of the audio, which explains why it
does not work with MLT today (each frame's audio is processed
individually). Not deleting these yet, however, in case we get them
working sometime in the next year.

svn path=/trunk/kdenlive/; revision=4829