Dont leak memory and do weird stuff

fosdem_video_progress.py

@@ -66,6 +66,7 @@ def main():
 		# We do not show jobstates atm. Too lazy.
 		# ys are transposed – we need vectors by times, not by states.
 		ys = list(zip(*ys))
+		plt.clf()
 		plt.stackplot(x, ys, labels=states)
 		plt.legend(loc='upper left')
 		print('showing plot')