[Feature Request] Add infoDistanceFormat and infoDistanceBlock

[clorl]

Use case : I'm bad at mental maths, so having the infoDistance is useful. However, I always make mistakes when using it to build certain sizes of walls, if I set the reference position a bit too "early" on the block, and I read the distance a bit too "late", the integer value won't be the block coordinate. It's a bit of a headache, I always make 1 or 2 block mistakes because of this. Also, it would be nice to be able to choose the display format just like the coordinateFormat.

Specs :

• Add distanceFormat as a string config entry so the display format of infoDistance can be specified by the player
• Add a way to have the block distance to the reference point rather than the actual distance. Maybe the easier way would be to have a boolean config entry named snapInfoDistanceToBlockCenter which would snap the distance reference point to its equivalent block position, same with the player's coordinates.

If you'd think that would be feasible with little knowledge of your codebase, I'd be happy to PR it.