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Hides award emoji & access level on system notes

## What does this MR do?

Hides award emoji & access level on system notes as they aren't applicable to them notes.

## Screenshots (if relevant)

![Screen_Shot_2016-06-13_at_16.14.03](/uploads/c105c37d0f140dea7480b56242c14ed9/Screen_Shot_2016-06-13_at_16.14.03.png)

See merge request !4629