allow binding of arguments for fg-commands thru run.cgi

allow binding of arguments for fg-commands thru run.cgi

to run a fg-command with args, POST run.cgi?value=my-command
and post the args node as JSON content like this:
{
   name: '',
   children: [
     {
       name: 'property',
       index: 0,
       value: 'first-value is here'
     },
     {
       name: 'property',
       index: 1,
       value: 'first-value is here'
     }
   ]
}
or whatever arguments the requested command takes