Added !last command, which gives the title of the last post on the subreddit
Surrounded command module execution with a try block
BotFactory now stores a list of bots it creates
Added the concept of a service which runs periodically instead of responding to a command
Added RedditService, which gives the title of each new post as it comes out
Fixed the configuration file from having a json extension, to a yml extension, as we are using yaml now
introduced a concept of main_context