Implemented a view for choosing pokemon

[Muaj17]

I created a view for choosing the pokemon. A few comments to be made

1. I didn't create a new JFrame, instead I built upon Yehyun's code where he removed everything from the main menu when "Start Game" was clicked. Then I added the ability to choose pokemon.
2. To test my code, you need to uncomment from Main.java: MenuView menuView = new MenuView(); and MenuView.displayMainView();. Then, as described above, when "Start Game" is clicked, the UI for choosing pokemon will appear.
3. @YehyunLee I removed the two buttons you told me to remove. Also, I commented out from GameView.java, lines 34-38 and line 45 because it appears to be some sort of button that should pop up when "Start Game" is clicked since it takes a while to load all the pokemon data, but nothing was popping out. Maybe this might be a bug on my end. You could look into it if you'd like.
4. @tyseer2335 I believe if you want to connect your BattleView or whatever view is next, you can use the selectedPokemonList that is stored when "Proceed" is clicked. Please check line 95 of GameView.java for an example. The problem is that I'm not sure if this is correct to do though, so maybe you can edit it so that it follows Clean Architecture more. Also you can the code if you want a popup instead of a transition from each view.
5. I feel the UI and code structure can be much better, but this is something we can work on if we have time.

EDIT: There have been issues made for some of the problems: #42 #44 #45 #47

[YehyunLee]

Okay, thanks for the contribution. I will take a closer look and comment more if any questions

[tyseer2335]

Nice, I will work on connect the BattleView