Status update adapter

This Pull request uses adapters to create messages and spread them.

it removes the functions:
 - create_message
 - fake_adapter

A default adapter is register for the INotifiable, interfaced that is attached to all the dexterity items and to StatusUpdate.

It addresses ticket #325 in assembla
noqa will make code_analysis pass.
IMHO there is no real point in staying strict to 80 chars when the price is readability and a code less readable.
That's why # noqa comment is there.

Another better alternative would be:
```
from ploneintranet.notifications.testing import (
    PLONEINTRANET_NOTIFICATIONS_INTEGRATION_TESTING
)
```

Is this breaking some of yout tests?