Service that connects to Meetup API and grabs/parses the group's events

## Usage

```python
from src.services.meetup.events import get_group_events

events = get_group_events()

print type(events)
"builtins.list"

print events[:2]
"""
[{'event_url': 'http://www.meetup.com/nycpython/events/126627152/',
  'name': 'nycpython.com mini-hackathon @ ChartBeat',
  'recurring': False,
  'time': datetime.datetime(2013, 6, 29, 8, 0)},
 {'event_url': 'http://www.meetup.com/nycpython/events/116381712/',
  'name': "Python study group (Can't make Saturdays? See Sunday's group)",
  'recurring': False,
  'time': datetime.datetime(2013, 6, 29, 8, 0)}]
"""
```

## Technical/main commit message

This commit adds a `src.services` and a `src.services.meetup` module.
The latter contains auxiliar classes in it that ultimately help `src.services.meetup.events.get_group_events` connect to Meetup and retrieve the group's events and return the basic information, including whether the event is recurring or not.