Added SMTP Collector and its client

ABOUT
======
Fake SMTP server.
The server here does not use authentication, but that might be implemented, too.

INTERFACE
==========
* 1025/TCP - smtp server
* 1026/TCP - json api

HOW TO TEST
============
Via py.test:
```bash
py.test -v -k send_test_email
ls -l log/emails/latest/test/send_test_email/
```

Or you can manually set up CFME, run:
```bash
python scripts/smtp_collector.py
```
send test e-mail manually and ask it:
```bash
curl "http://localhost:1026/messages"
```
Script is gracefully killed with `^C`