Canvas Smart Contract

[Braqzen]

Contract should contain at least the following functionality:

• Fixed size canvas
  • Clearing all the slots would be expensive so once the canvas is created we cannot create a new one unless we perform some indexing up to the maximum u64 size to create a few canvases per contract. Better to stick with a single canvas for now.
  • Index pixels by a u64 for ease of use
• Each pixel is represented by some colour format e.g. rgb
• Getter to return a pixel colour
• Setter to set a pixel colour
• Initial implementation does not need to require a time delay between each placement
• Getter to return the maximum canvas size

[bitzoic]

Closing to consolidate to just #559