Add module IM, testing messaging services (hipchat included)

Adding a IM module, to support testing with instant messaging services. Currently supporting HipChat testing.

### Supported Functions
- Send Message
- Test against last message.

### Example (IMCept.php)
```php
<?php
$I = new IMGuy($scenario);
$I->wantTo('grab the recent messages on the IM server and run some tests');

$message = $I->grabLastInstantMessage();
$I->seeInLastInstantMessageFrom('Tester');
$I->dontSeeInLastInstantMessageFrom('Codeception');
$I->seeInLastInstantMessageContent('Testing has been completed with no issues.');
$I->dontSeeInLastInstantMessageContent('Random Message not there');
$I->seeInLastInstantMessageColor('yello');
$I->dontSeeInLastInstantMessageColor('red');
$date = $I->grabLastInstantMessageDate();
$I->seeInLastInstantMessageDate('2014-10-21T16:41:48.657455+00:00');
$I->dontSeeInLastInstantMessageDate('2015-10-21T16:41:48.657455+00:00');

$I->sendInstantMessage("Testing has been completed with no issues.", array('color' => 'yellow', 'notify' => true));

```