Add isort pre-commit hook

Sort import statement in python files

See https://github.com/PyCQA/isort

utils/airtime-import/airtime-import

@@ -1,12 +1,13 @@
 #!/usr/bin/python2 import sys
-import os
-import logging
-from configobj import ConfigObj
-from optparse import OptionParser, OptionValueError
-from api_clients import api_client as apc
 import json
+import logging
+import os
 import shutil
+from optparse import OptionParser, OptionValueError
+
 import commands
+from api_clients import api_client as apc
+from configobj import ConfigObj
 
 # sys.path.append('/usr/lib/airtime/media-monitor/mm2/')
 from mm2.media.monitor.pure import is_file_supported

utils/airtime-silan

@@ -1,14 +1,14 @@
 #!/usr/bin/python
-from configobj import ConfigObj
-from api_clients import api_client as apc
-
-import logging
 import json
+import logging
 import os
-import sys
 import subprocess
+import sys
 import traceback
 
+from api_clients import api_client as apc
+from configobj import ConfigObj
+
 # create logger
 logger = logging.getLogger()
 

utils/airtime-test-soundcard.py

@@ -1,11 +1,10 @@
-import subprocess
+import getopt
+import grp
 import os
 import pwd
-import grp
+import subprocess
 import sys
 
-import getopt
-
 """
 we need to run the program as non-root because Liquidsoap refuses to run as root.
 It is possible to run change the effective user id (seteuid) before calling Liquidsoap

utils/airtime-test-stream.py

@@ -1,11 +1,10 @@
-import subprocess
+import getopt
+import grp
 import os
 import pwd
-import grp
+import subprocess
 import sys
 
-import getopt
-
 """
 we need to run the program as non-root because Liquidsoap refuses to run as root.
 It is possible to run change the effective user id (seteuid) before calling Liquidsoap

utils/upgrade.py

@@ -1,10 +1,11 @@
 #!/usr/bin/python
 
-import ConfigParser
 import argparse
+import sys
+
+import ConfigParser
 import requests
 from urlparse import urlparse
-import sys
 
 CONFIG_PATH = "/etc/airtime/airtime.conf"
 GENERAL_CONFIG_SECTION = "general"