Subdir

Allows us to host the app on a subdirectory.

This will be /employment-tribunals. Or whatever's set as RAILS_RELATIVE_URL_ROOT.

Unfortunately we have a bunch of static links in our locale file. Is it rendered anywhere i.e. can we use the environment variable somehow?
Oh dear, sorry @mattmb these paths should simply never have been hard coded in the first place. These strings should look like

```ruby
has_additional_claimants: For up to 5 other claimants you can enter their details <a href="%{path}">manually</a>
```

And used like:

```ruby
t(:has_additional_claimants, path: claim_additional_claimants_path)
```

Strings containing html should have keys suffixed with `_html` this way the contents are not escaped and won't have to be marked as html safe when used.

Do a git blame and ask the perp to fix this :)