Change default language to English

Because we have international members now and we shouldn't force them to switch to English.

https://gitlab.science.ru.nl/thalia/concrexit/blob/master/website/thaliawebsite/settings/settings.py#L197 The default language is Dutch, so this means that devices set to a non-Dutch/English language automatically select it as fallback.

The default language should be English, so this means that devices set to a non-Dutch/English language automatically select it as fallback.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information