This fixes email threading in Mail.app, that doesn't like when a thread
doesn't have stable recipients.
For instance, here is a possible sender-recipient combinations before:
From: A
To: Me
New issue
From: B
To: Me
Reply on new issue
From: A
To: Me
Another reply
Mail.app doesn't see B as a participant to the original email thread,
and decides to break the thread: it will group all messages from A
together, and separately all messages from B.
This commit makes the thread look like this:
From: A
To: gitlab/project
Cc: Me
New issue
From: B
To: gitlab/project
Cc: Me
Reply on new issue
From: A
To: gitlab/project
Cc: Me
Another reply
Mail.app sees a common recipient, and group the thread correctly.
When an email notification concerns a specific object (issue, note,
merge request, etc.), add a link to the footer of the email that opens
the item's page in a web browser.
Rationale:
* The link is predictable: always the same text, always at the same
location, like any reliable tool.
* It allows to remove the inline-title in many emails, and leave only
the actual content of the message.
This changes the email "From" field from "gitlab@example.com" to either:
* "John Doe <gitlab@example.com>" if the author of the action is known,
* "GitLab <gitlab@example.com>" otherwise.
Rationale: this allow mails to appear as if they were sent by the
author. It appears in the mailbox more like a real discussion between
the sender and the receiver ("John sent: we should refactor this") and
less like a robot notifying about something.
There was some funny syntax in merge request email templates. There was a ! before
the merge request number when there probably should be a #. This may be some carry over
from markdown but should not be in email templates. There were also some capitalization
discrepancies among the subject lines. For those OCD people out there I standardized the
capitalization. :)
