reformat compute pressure/cylinder docs and integrate it into the manual

[Description:]

Define a computation that calculates the pressure tensor of a

system in cylindrical coordinates, as discussed in "(Addington)"_#Addington1.

Define a computation that calculates the pressure tensor of a system in

cylindrical coordinates, as discussed in "(Addington)"_#Addington1.

This is useful for systems with a single axis of rotational symmetry,

such as cylindrical micelles or carbon nanotubes. The compute splits 

the system into radial, cylindrical-shell-type bins of width bin_width, centered at x=0,y=0,

and calculates the radial (P_rhorho), azimuthal (P_phiphi), and axial (P_zz) components of the configurational pressure

tensor. The local density is also calculated for each bin, so that

the true pressure can be recovered as P_kin+P_conf=density*k*T+P_conf.

The output is a global array with 5 columns; one each for bin radius,

local number density, P_rhorho, P_phiphi, and P_zz. The number of 

rows is governed by the values of Rmax and bin_width. Pressure

tensor values are output in pressure units.

such as cylindrical micelles or carbon nanotubes. The compute splits the

system into radial, cylindrical-shell-type bins of width bin_width,

centered at x=0,y=0, and calculates the radial (P_rhorho), azimuthal

(P_phiphi), and axial (P_zz) components of the configurational pressure

tensor. The local density is also calculated for each bin, so that the

true pressure can be recovered as P_kin+P_conf=density*k*T+P_conf.  The

output is a global array with 5 columns; one each for bin radius, local

number density, P_rhorho, P_phiphi, and P_zz. The number of rows is

governed by the values of Rmax and bin_width. Pressure tensor values are

output in pressure units.

[Output info:]

"units"_units.html. The number density values will be in 

inverse volume "units"_units.html.

[Restrictions:] This compute currently calculates the pressure 

tensor contributions for pair styles only (i.e. no bond, dihedral, etc.)

and requires pair force 

calculations not available for many manybody pair styles. K-space 

calculations are also excluded. Note that the pressure outputs 

are the configurational terms only; the kinetic contribution may

be calculated from the number density output by P_kin=density*k*T.

[Restrictions:]

This compute currently calculates the pressure tensor contributions

for pair styles only (i.e. no bond, angle, dihedral, etc. contributions

and in the presence of bonded interactions, the result will be incorrect

due to exclusions for special bonds)  and requires pair-wise force

calculations not available for most manybody pair styles. K-space

calculations are also excluded. Note that this pressure compute outputs

the configurational terms only; the kinetic contribution is not included

and may be calculated from the number density output by P_kin=density*k*T.

This compute is part of the USER-MISC package.  It is only enabled

if LAMMPS was built with that package.  See the "Build

package"_Build_package.html doc page for more info.

[Related commands:]

   compute_pe_atom

   compute_plasticity_atom

   compute_pressure

   compute_pressure_cylinder

   compute_pressure_uef

   compute_property_atom

   compute_property_chunk

compute_pe_atom.html

compute_plasticity_atom.html

compute_pressure.html

compute_pressure_cylinder.html

compute_pressure_uef.html

compute_property_atom.html

compute_property_chunk.html