Add "end game" and "add word" buttons to Madlibs

[DMFriends]

Description

After #901 was merged, I thought of 2 more ideas that I think might be cool to add to the Madlibs game.

1. Add an "end game" button to end the game in case a user decides not to play after starting a game.
2. Add an "add word" button that randomly chooses a word from a list of words and adds it to the game in case the user can't think of a good word to use for the game.

Reasoning

I think these features will enhance how this game works and I'm sure it will make the game more fun to play.

Proposed Implementation

For the random word list, I plan to use the already existing hangman_words.txt file and just rename it to random_word_list.txt so it can be used anywhere, not just hangman or madlibs.

Would you like to implement this yourself?

• [x] I'd like to implement this feature myself
• [ ] Anyone can implement this feature