Fix precision in blocks (Super Mario Bros. 3, Super Mario World)

[meduzen]

Can’t unsee.

Might depend on the zoom level of the browser.
Possible causes:

• browser messing with roundings;
• despite the block viewBox being 512×512, some of its element might have too little precision following the compression (likely <path> elements, unlikely <rect>);
• ?

Super Mario Bros. 3

• Unwanted micro-space below the square at (2,2).

view screenshot

• Unwanted micro-space before the last column.

view screenshot

Super Mario World

• Unwanted micro-space at the right of the first and fifth columns.

view 2 screenshots

• Unwanted micro-space at the bottom of the second row.

view screenshot

• Unwanted micro-space at the right of the second eye.

view screenshot