Custom email notification

[Yosirion]

I think that it could be useful to add the possibility to customize the emails that thephish send to the users that forwarded the email. One way could be to add in the json file configuration.json or in a new json file something like that

 "email" : {
                 "notification" : "Notification text. [{0}] to include the subject of the email",
                 "safe" : "Safe email text. [{0}] to include the subject of the email",
                 "malicius" : "Malicius email text. [{0}] to include the subject of the email"
        }

The suspicius case is not included because the email notification isn't automatic.
A possible change to the code could be:

task_notification = thehive4py.models.CaseTask(
                                        id=task_id,
                                        description = "mailto:" + mail_to + "\n" + config['notification'].format(case.json()['title'][11:]),
                                        status = 'InProgress'
                                        )

Where config['notification'] is equal to the value of the object Notification.

[emalderson]

Thanks for the suggestion. I'll consider adding this feature in a future commit.