Fixed small bug in chapter import handler

chapters.py

@@ -3,7 +3,7 @@ from server import *
 
 @job_handler('probe', 'probe-raw')
 def import_xmp_chapters(jobid, jobtype, data, state, status):
-	if 'lecture_id' not in data and data.get('import-chapters', False):
+	if 'lecture_id' not in data or not data.get('import-chapters', False):
 		return
 	times = set()
 	# Only add new chapters, deleted chapters are taken into account here