Adding a .csv CAN logger example

Logs on all 3 CAN busses to output.csv

examples/can_logger.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+import binascii
+import csv
+from panda import Panda
+
+def can_logger():
+  
+  try:
+    p = Panda()
+  
+    outputfile = open('output.csv', 'wb')
+    csvwriter = csv.writer(outputfile)
+    #Write Header
+    csvwriter.writerow(['Bus', 'MessageID', 'Message'])
+    print("Writing csv file. Press Ctrl-C to exit...")
+
+    while True:
+      can_recv = p.can_recv()
+      for address, _, dat, src  in can_recv:
+        csvwriter.writerow([str(src), str(address), binascii.hexlify(dat)])
+
+  except KeyboardInterrupt:
+    print("Exiting...")
+    outputfile.close()
+
+if __name__ == "__main__":
+  can_logger()