VrRecruit Final Changes

Here is my take on both tasks.

The answer guessing code is stored in file `Str.php`. I commented my line of thought in how to do the guessing for positive and negative answers. 
The function can return 3 statuses, `Accepted`, `Refused` and `Unknown`. I think `Unknown` can be very useful for failed guess (by not having the keyword or being ambiguous) and then the manager can easily find such task and manually see the answer.

On the front-end I added a sorting drop down button and text search box to improve usability of the tool. `Accepted` and `Refused` task are colored marked to easily spot them.
Same colouring happens in the task view where you can see the message that triggered the status change.
An status change button could be implemented, but it would depend on how a task is marked as `Done`.
`Done` status could be manually changed by manager or agent, or maybe by sending an sms with the word Done (and use the guess function to guess this state as well).

Please let me know if you have any questions
@brutuscat it probably makes more sense to have all this under createAction than index. If the task_id would come in the message (for example first word is always task_id), then we just need to call a function in the model to get the id from text and then get the task. In the createAction we only would be storing message, tasklog and update the task (these last two after guessing the answer).