Wiki requires fix

[Smoria]

Wiki requires small fix:

Part with must hold at least width x 16 bytes must include some description that width must be rounded to next divisible by 16 number. i.e. buffer for image with width = 15 must be at least 16*16.

Steps to reproduce the behavior:

1. Try to decode any image with width not divisible by 16, providing dithering buffer with size of image.width*16
2. Heap is corrupted after decoding

Tested with ESP-32, so we actually have heap supervisor.

Sorry for creating issue, and not PR, i am not able to use git right now :)