Resolved - Add calc command to Junco code

This simply uses the Perl eval command to process an arithmetic string.

Format:  calc = arithmetic expression. 

After the eval is processed, the calc command is surrounded with brackets and included in the output.

calc=(5+3)  / 2

calc=440 * .4

calc=440 * .6

calc=7/5

Here's an intentional syntax error:

calc=5(3

Need to work out the formatting kinks a little, but if I want a quick calculation, this will suffice.

 #junco - #resolved