Add options to config log file

example_conf.json

@@ -1,5 +1,9 @@
 {
     "host": "localhost",
+    "log_file_name": "pyapns.log",
+    "log_file_dir": ".",
+    "log_file_rotate_length": 1000000000,
+    "log_file_max_rotate": 10,
 	"port": 7077,
 	"rest_port": 8088,
 	"autoprovision": [

pyapns.tac

@@ -6,6 +6,8 @@ config_file = '/path/to/config/pyapns_conf.json'
 # you don't need to change anything below this line really
 
 import twisted.application, twisted.web, twisted.application.internet
+from twisted.python.logfile import LogFile
+from twisted.python.log import ILogObserver, FileLogObserver
 import pyapns.server, pyapns._json
 import pyapns.rest_service, pyapns.model
 import os
@@ -33,7 +35,34 @@ if 'autoprovision' in config:
             timeout=app['timeout']
         )
 
+if 'log_file_name' in config:
+    log_file_name = config['log_file_name']
+else:
+    log_file_name = 'twistd.log'
+
+if 'log_file_dir' in config:
+    log_file_dir = config['log_file_dir']
+else:
+    log_file_dir = '.'
+
+if 'log_file_rotate_length' in config:
+    log_file_rotate_length = config['log_file_rotate_length']
+else:
+    log_file_rotate_length = 1000000
+
+if 'log_file_mode' in config:
+    log_file_mode = config['log_file_mode']
+else:
+    log_file_mode = None
+
+if 'log_file_max_rotate' in config:
+    log_file_max_rotate = config['log_file_max_rotate']
+else:
+    log_file_max_rotate = None
+
 application = twisted.application.service.Application("pyapns application")
+logfile = LogFile(log_file_name, log_file_dir, log_file_rotate_length, log_file_mode, log_file_max_rotate)
+application.setComponent(ILogObserver, FileLogObserver(logfile).emit)
 
 if 'host' in config:
     host = config['host']