For setting the night mode, it checks to see if you’re in development
by checking `page_params.development`, but the actual attribute is
`page_params.development_environment`.
We should use variables in i18n strings to give proper context to the
translators. If the pattern is this:
```
i18n.t("Count " + count + " items")
```
Then it will be captured like this:
```
{"Count" + count + "items": ""}
```
Which is not good for the translators.
Note that this code is disabled until the infrastructure for the
feature can be finished.
Tweaked by tabbott to use slightly cleaner names for the various sets.