Add cpu_load_percent segment

This requires psutil to be installed, should be added to the docs later.

powerline/colorschemes/tmux/default.json

@@ -24,6 +24,7 @@
 		"system_load_good": { "fg": "green", "bg": "darkestblue" },
 		"system_load_bad": { "fg": "yellow", "bg": "darkestblue" },
 		"system_load_ugly": { "fg": "red", "bg": "darkestblue" },
+		"cpu_load_percent": { "fg": "brightblue", "bg": "darkestblue" },
 		"uptime": { "fg": "brightblue", "bg": "darkestblue" }
 	}
 }

powerline/segments/common.py

@@ -130,6 +130,15 @@ def system_load(format='{avg[0]:.1f}, {avg[1]:.1f}, {avg[2]:.1f}'):
 	}
 
 
+def cpu_load_percent(measure_interval=.5):
+	try:
+		import psutil
+	except ImportError:
+		return None
+	cpu_percent = int(psutil.cpu_percent(interval=measure_interval))
+	return u'{0}%'.format(cpu_percent)
+
+
 def network_load(interface='eth0', measure_interval=1, suffix='B/s', binary_prefix=False):
 	import time
 	from powerline.lib import humanize_bytes

powerline/themes/tmux/default.json

@@ -21,6 +21,9 @@
 			{
 				"name": "system_load"
 			},
+			{
+				"name": "cpu_load_percent"
+			},
 			{
 				"name": "weather"
 			},