Removed unused code.
Don't display timeline link if there's nothing to be shown.
Small cleanup.
Improved code readability.
Use the same time for all submissions.
Attribute proper submission information upon suggestion approval.
Display reviewer information for translations based on suggestions.

The implementation is quite lame due to shortcomings of the underlying DB
schema, but since the data is there we are able to query it without further
changes for now. Bug 2712 has been filed for further improvements over the
backend.

Fixes bug 2406.