Remove run_once from ShellPowerline, fix update_first

run_once will be passed to Powerline as a part of **kwargs

powerline/lib/threaded.py

@@ -35,7 +35,6 @@ class ThreadedSegment(object):
 			#
 			# If running once .update() is called in __call__.
 			if update_first and self.update_first:
-				self.update_first = False
 				self.update()
 			self.start()
 

powerline/shell.py

@@ -14,10 +14,10 @@ def mergeargs(argvalue):
 
 
 class ShellPowerline(Powerline):
-	def __init__(self, args, run_once=False, **kwargs):
+	def __init__(self, args, **kwargs):
 		self.args = args
 		self.theme_option = mergeargs(args.theme_option) or {}
-		super(ShellPowerline, self).__init__(args.ext[0], args.renderer_module, run_once=run_once, **kwargs)
+		super(ShellPowerline, self).__init__(args.ext[0], args.renderer_module, **kwargs)
 
 	def load_main_config(self):
 		r = super(ShellPowerline, self).load_main_config()