Updated error code comparison when handling ProcessExceptions with hg commands.

Author: cmonr

mbed/mbed.py

@@ -520,7 +520,7 @@ def outgoing():
             pquery([hg_cmd, 'outgoing'])
             return 1
         except ProcessException as e:
-            if e[0] != 1:
+            if e.args[0] != 1:
                 raise e
             return 0