Various changes & bug fixes

A few changes:

• Stool -> Chair. This was changed to teach a more generic and usable word, this word's mastery progress has been reset.
• 2 typo fixes
• 2 Small signs at the convenience stores have been updated to retain an E for Everyone rating
• Fixed a bug regarding the quiz mode selection on controller
• The Find/Quiz Mode menu now has a small animation to show that it can be swapped more clearly.
• The "Export Favourites" button in the pause menu now has an icon