makefile and rc.local fix

cmd/audio-player/looper/Makefile

@@ -4,6 +4,7 @@ PATH := /usr/local/go/bin:$(PATH)
 
 .SILENT:copy_files
 .SILENT:hard_copy_files
+.SILENT:build
 .SILENT:clean
 
 install: as_root copy_files build

cmd/audio-player/looper/rc.local

@@ -0,0 +1,15 @@
+#!/bin/sh -e
+# /etc/rc.local
+# This script launches audio looper at boot time
+
+exec 2> /tmp/rc.local.log      # send stderr from rc.local to a log file
+exec 1>&2                      # send stdout to the same log file
+printf "rc.local started"      # show start of execution
+set -x                         # tell sh to display commands before execution
+
+PLAYERPATH=/home/pi/go/src/bitbucket.org/ausocean/av/cmd/audio-player/looper
+cd $PLAYERPATH
+
+./looper &
+
+exit 0