Move array mixin methods into CoreMongooseArray

[vkarpov15]

No description provided.

[vkarpov15]

Basic benchmark:

'use strict';

const Benchmark = require('benchmark');
const mongoose4 = require('mongoose');
// Note this is not the actual mongoose 5 npm module, this is just
// a symlinked alias for the purposes of this benchmark
const mongoose5 = require('mongoose-56');

const suite = new Benchmark.Suite;

const M4 = mongoose4.model('Test', new mongoose4.Schema({ arr: [String] }));
const M5 = mongoose5.model('Test', new mongoose5.Schema({ arr: [String] }));

suite.
  add('mongoose4', function() {
    new M4({ arr: ['foo', 'bar', 'baz'] });
  }).
  add('mongoose5', function() {
    new M5({ arr: ['foo', 'bar', 'baz'] });
  }).
  on('cycle', function(event) {
    console.log(String(event.target));
  }).
  on('complete', function() {
    console.log('Fastest is ' + this.filter('fastest').map('name'));
  }).
  run();

Output:

$ node queryperf.js 
mongoose4 x 79,094 ops/sec ±0.81% (89 runs sampled)
mongoose5 x 107,371 ops/sec ±0.98% (89 runs sampled)
Fastest is mongoose5
$