Fix sound recording bug

The bug was in Palaso.Media.AudioAlsaSession.LastRecordingMilliseconds,
and reported as FWNX-1071.  A new set of Palaso DLLs generated by
TeamCity on the fixed code fixes this bug.

Cherry picked from develop branch.

Change-Id: Ie6aff498bebbbb7c39b2b32fd3d1c9ac6f080577