Add support for downloading most language codes, and if we don't have it default to english

[mitchcapper]

Someone contacted about it not working off GH and I found the issue was an alternate locale problem. Here is a lost of all the valid locales for matterport I could find and if we don't have the locale in question default to the english file. Note that locale switch only works with the embedded server.

[rebane2001]

@mitchcapper fyi I gave you repo access, so you can feel free to commit directly or accept PRs yourself if you wish