[refactor] Cleanup code

- Rename joystick library to helpers
- Put color565 function in helpers.py
- Switch screen width and height names as game runs in landscrape
- Enumerate levels for readability
- Update docstrings
- Rework splash screen to use binary operators
- Extract create bricks and create lives functions
- Reowrk main game loop logic to support next level

joystick.py

@@ -1,12 +0,0 @@
-from machine import Pin
-class Joystick:
-    def __init__(self):
-        # Map buttons
-        self.button_a = Pin(15, Pin.IN, Pin.PULL_UP)
-        self.button_b = Pin(17, Pin.IN, Pin.PULL_UP)
-        # Map joystick
-        self.joy_up = Pin(2,Pin.IN, Pin.PULL_UP)
-        self.joy_down = Pin(18,Pin.IN, Pin.PULL_UP)
-        self.joy_left = Pin(16 ,Pin.IN, Pin.PULL_UP)
-        self.joy_right = Pin(20 ,Pin.IN, Pin.PULL_UP)
-        self.joy_click = Pin(3, Pin.IN, Pin.PULL_UP)