difficulty options and QOL stuff

OK so i added a few things

• difficulty options, they just lower/increase the amount of damage you do but now if someone calls the game easy i can say “go beat boss rush 3 on hard nerd” instead of just “go beat boss rush 3 nerd”
• menus are now WAY faster. persona 5 type stuff. it’s almost twice as fast.
• NEW menu noises that AREN’T annoying
• menu noises don’t play anymore when you’re selecting a song in the sound test
• the toilet miniboss in level 2 has DOUBLE his original health and is therefore half as pathetic
• r isn’t the only key that plays a funny noise in the main menu anymore. have fun