Updated the translations for reCAPTCHA

Mainly because lately it doesn't give always two words, but only one so asking to `Type the two words` was misleading. So I took the complete list from: https://www.google.com/recaptcha/api/js/recaptcha.js and added the missing ones as well.

- Added `privacy_and_terms`, `image_alt_text` to the translations
- Removed the `:` from text
- Changed all the text to match exactly the original source
- Sorted by name
Merge pull request #146 from lipis-z/patch-1

Updated the translations for reCAPTCHA