Legend array size option

It is possible to exceed the legend array size for bonded terms, i.e. from mxb = 6 which gives 24 as the maximum length for angle potentials:

    Subroutine scan_field(...)
    ...
    Integer, Parameter :: mmk = 1000, mxb = 6
    ....
    !> this may end up in forced conversion not all squares are divisible by 2...
    If (angle%max_angles > 0) angle%max_legend = (mxb + 1)**2 / 2 + 1
    mxf(7) = angle%max_legend
    ...

this could be an option in CONTROL for the new style format, allowing a user to set this value.