MT#5879 Send invoices via email.

Text of the message should be conformed with sales. Also it would be nice to apply templates to email body.
Only smarthost is working, spent 3 hours with exim debug and while left with smarthost. Attachments and so one looks good.
Removed fake data.
Fix data parameter. Tested data and client contracts.
MT#5879 Fix creating of datetime with full parameters.

Zone can be moved to class variable?Later.