Feature/create client

I'm not sure about using a shell variable to store the token. Right now we mostly generate the tokens statically (through the Canvas settings page). In general, though, that's not the correct way to get the token. It's going to be more likely that people get the token through the OAuth token request dance, which means that it'll be stored in memory. At that point it makes more sense to pass it in as a parameter rather than through the shell.