* FEATURE: Account for `ignored_users` when merging two users
## Why?
This is part of the [Ability to ignore a user feature](https://meta.discourse.org/t/ability-to-ignore-a-user/110254/8).
When we merge two users, we need to account for merging their list of `ignored_users` too.
- Notices are visible only by poster and trust level 2+ users.
- Notices are not generated for non-human or staged users.
- Notices are deleted when post is deleted.
It seems that due to jobs being asynchronous and wrapping code in a
DistributedMutex that by the time we run the
`UserAvatar#update_gravatar!` job that the user/user email might be
destroyed.
This patch checks before a call to `user.email_hash` to make sure
the user and primary email exist to prevent the exception. If not
present, the job exits as there's nothing to do because we are
probably running after the user was destroyed for some reason.
Now you can also make authenticated API requests by passing the
`api_key` and `api_username` in the HTTP header instead of query params.
The new header values are: `Api-key` and `Api-Username`.
Here is an example in cURL:
``` text
curl -i -sS -X POST "http://127.0.0.1:3000/categories" \
-H "Content-Type: multipart/form-data;" \
-H "Api-Key: 7aa202bec1ff70563bc0a3d102feac0a7dd2af96b5b772a9feaf27485f9d31a2" \
-H "Api-Username: system" \
-F "name=7c1c0ed93583cba7124b745d1bd56b32" \
-F "color=49d9e9" \
-F "text_color=f0fcfd"
```
There is also support for `Api-User-Id` and `Api-User-External-Id`
instead of specifying the username along with the key.
When a plugin registers a language and sets fallbackLocale="en", fallback strings were missing. This commit strips any duplicate ":en" symbols when loading merged translations.
