[IMP] mass_mailing: allow users to choose a specific outgoing mail server

Purpose of this commit is to allow mass mailing users to select an outgoing
mail sever when performing mass mailing. It includes

* add a field in mass_mailing to select specific outgoing mail server;
  it is put in debug mode because it sounds people would not understand
  what is its purpose;
* add an option in settings to set a default outgoing mail server;
* give read access to ir.mail_server to mass_mailing users;

This commit is related to task ID 31737.

0 files changed, 0 insertions, 0 deletions