cc-2055: switch to init.d

-allow install script to be created from any location (no hardcoded paths)
-make python install scripts return 1 on error
-daemon now started automatically on boot using rc.local autostart
-change all prints to logs instead
-create airtime-uninstall shell script (and remove pypo user in here)
-create pypo user in shell script

python_apps/create_pypo_user.py

@@ -0,0 +1,29 @@
+import os
+from subprocess import Popen, PIPE, STDOUT
+
+def create_user(username):
+  print "Checking for user "+username
+  
+  p = Popen('id '+username, shell=True, stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
+  output = p.stdout.read()
+  
+  if (output[0:3] != "uid"):
+    # Make the pypo user
+    print "Creating user "+username
+    os.system("adduser --system --quiet --group --shell /bin/bash "+username)
+    
+    #set pypo password
+    p = os.popen('/usr/bin/passwd pypo 1>/dev/null 2>&1', 'w')
+    p.write('pypo\n')
+    p.write('pypo\n')
+    p.close()
+  else:
+    print "User already exists."
+  #add pypo to audio group
+  os.system("adduser " + username + " audio 1>/dev/null 2>&1")
+  #add pypo to www-data group
+  os.system("adduser " + username + " www-data 1>/dev/null 2>&1")
+
+
+if __name__ == "__main__":
+    create_user("pypo")