Allow value to be specified in add_field #4
Description
The current syntax of the add_field command is as follows: add_field class node field [capacity]
It has been suggested that the command should be modified to allow a value to be specified, like so: add_field class node field [value]
This presents a problem - the ideal position for the value argument is already taken by the optional array capacity argument. The easiest solution to this problem is to simply give the argument two possible meanings. The new syntax definition would be as follows: add_field class node field [capacity OR value]
An array does not have a value, so the optional argument would be interpreted as a capacity. Non-arrays do not have capacities, so the optional argument would be interpreted as a value.