ATC: fix_modify AtC mesh output

# fix_modify AtC mesh output

## syntax

fix_modify AtC mesh output <file_prefix>

## examples

`fix_modify AtC mesh output meshData`

## description

Command to output mesh and associated data: nodesets, facesets, and elementsets. This data is only output once upon initialization since currently the mesh is static. Creates (binary, "gold" format) Ensight output of mesh data.

## restrictions

none

## related

## default

none