Migrate securesync from e.message to e.args[0]

Fix for #2020 

Simply changed e.message to e.args[0] everywhere it's found in securesync, so we shouldn't get the deprecation message when we run a cron job. 

@aronasorman it still exists in these locations:

![image](https://cloud.githubusercontent.com/assets/1319950/2856215/80609986-d166-11e3-9367-3d6b7bd19a09.png)

Let me know if you think it's wise to clean them out in places that are not django, like distributed/api_views, etc.