correct formatting for examples when discussing the non-incremental nature of special_bonds

time incrementally.  E.g. these two commands:

special_bonds lj 0.0 1.0 1.0

special_bonds coul 0.0 0.0 1.0

special_bonds coul 0.0 0.0 1.0 :pre

are not the same as

special_bonds lj 0.0 1.0 1.0 coul 0.0 0.0 1.0

special_bonds lj 0.0 1.0 1.0 coul 0.0 0.0 1.0 :pre

In the first case you end up with (after the 2nd command):

LJ: 0.0 0.0 0.0

Coul: coul 0.0 0.0 1.0

Coul: 0.0 0.0 1.0 :pre

because the LJ settings are reset to their default values

each time the command is issued.

while only in the second case, you get the desired settings of:

LJ: 0.0 1.0 1.0

Coul: 0.0 0.0 1.0 :pre

This happens because the LJ (and Coul) settings are reset to

their default values before modifying them, each time the

{special_bonds} command is issued.

[Restrictions:] none