1.18.2r2

• Replaced almtx_, alcnd_ and altss_* functions with code not using
  pthreads.

• Changed ALCplaybackAHI_stop() to periodically check if the mixer process has
  ended rather than relying on the death signal. This fixes uqm hanging on
  exit when used with openal because ALCplaybackAHI_start() was called from
  a different process.

1.18.2-20180222

• First released version.