Fix obsolete comment

Author: ExplodingCabbage

gitignore_plugin.py

@@ -22,8 +22,7 @@
 
 def start(): # Gets invoked at the bottom of this file.
     """
-    Regularly (every 5s) updates the file_exclude_patterns setting from a
-    background thread.
+    Regularly (every 5s) updates the file_exclude_patterns setting.
     """    
     if is_first_launch():
         migrate_exclude_patterns()
@@ -226,4 +225,4 @@ def windows_path_to_sublime_path(path):
     without_colon = path[0] + path[2:]
     return without_colon.replace(u'\\', u'/')
 
-start()
+start()