update .gitignore

Remove coverage directory from repository
Setup Basic Sinatra app

- Add usual gems for styling and client side
- update assets to include the bootstrap files
- setup layout
Setup Rspec

Add spec helper and define game boards for use in tests
Add the AI class

This controls the ai for the game which implements a minimax algorithm
Add the Board class

A shell for a board in the game. loads all of the game cells into the
board for comparison later to check for wins.
Add Game class

Master class that controls the game and works as a store for game
state.
Add front end

adds game css and JS for controlling the board as well as the board
itself
Add route and assets to app

Add the api route for the AI move to communicate with the client.

Also add in assets to the application to load