Removed unused source files from solaris makefile.
Increase squeezelite revision to 399.
Fix gapless playback for portaudio (06da65c9871ef6eebe2f49b9d51c0c9e101ecdd8)
Increase squeezelite revision to 400.
Bump squeezelite version to 1.6 (1ca20695176cb1d970d01ca47d5d27d85d540857)
Increase squeezelite revison to 401.