Documentation example is confusing

[thejsj]

First of all, thanks for doing this! This npm module seems pretty interesting. I personally don't use koa, but just wanted to make a quick suggestion to your documentation.

I like the simplicity of your example, but the variable naming is a bit confusing. Let me try to explain why with comments...

var koa = require('koa')
// for use with koa-generic-session
var session = require('koa-generic-session')
var RethinkSession = require('koa-generic-session-rethinkdb')
/*!
 * In most example of rethinkdbdash, the code used to instanstiate it is the following:
 * `var r = require('rethinkdbdash')();`
 * The fact that this is different (only by two parenthesis is already a little confusing!). 
 * That being said, naming it to `rethinkdb` seems appropriate
 */
var rethinkdb = require('rethinkdbdash')

/*!
 * What the function returned by importing `rethinkdbdash` returns is not really a connection. 
 * It's more an instance of rethinkdbdash which actually has a connection pool, which actually 
 * has multiple connections. Using the word connection is not totally off, but (by convention) 
 * most people use the `r` variable here. Not using the `r` variable somehow seems to suggest that
 * this is different, when this is actually not.
 */ 
var connection = rethinkdb({
  host: 'localhost',
  port: 28015
})

var sessionStore = new RethinkSession({connection: connection})
// create the db, table and indexes to store sessions
sessionStore.setup()

var app = koa()
// used for cookie stuffs
app.keys = ['foo', 'bar']

app.use(session({
  store: sessionStore
})

I suggest the following:

var koa = require('koa')
// for use with koa-generic-session
var session = require('koa-generic-session')
var RethinkSession = require('koa-generic-session-rethinkdb')
var r = require('rethinkdbdash')({
  host: 'localhost',
  port: 28015
});

var sessionStore = new RethinkSession({connection: r })
// create the db, table and indexes to store sessions
sessionStore.setup()

var app = koa()
// used for cookie stuffs
app.keys = ['foo', 'bar']

app.use(session({
  store: sessionStore
})

Again, thanks for taking time to work on this! Just had an issue with a user who got a little confused because of the variable naming and thought others might have run into this. I might also be totally wrong about all this and missing something :). Thanks!