Custom number of columns, column grouping interval and making strict offset alignment optional.

[comandantelimones]

Tried to make the hex grid more flexible by adding a few things here:

1. Option to specify the number of columns in the grid (default is the previously hardcoded 16 bytes)
2. Column grouping interval (default is the previously hardcoded space per eight bytes)
3. Removing a strict requirement of grid alignment (to be able to display stuff from a position that is not a multiple of the number of grid columns)

All of those are tweaked using the initial grid options. All are optional and default to the original behaviour.