Refactor into a library

[karlroberts]

Hi Bryan,

I love the code so far. I have a suggestion.

1. Have you considered refactoring it into a multi module sbt project, with most of the code in an slack-scala-lib jar with the Main class in a separate examples module?

This would be cool, because then the example usage is a small bit of code that simply depends on the lib.

Because the surface area of the example is now small, you/we/I could create a giter8 example that would allow people to simply do g8 gilbertw1/slack-bot.g8 and in minutes have a standalone working chat bot for themselves.

If you like I'll fork a branch to demonstrate.

Cheers

Karl