[feature request] ignore unnumbered lines that begin with a semicolon `;` character

[jeffgazso]

It would be nice if the interpreter ignored unnumbered lines that begin with the semicolon ; character. This is most useful for embedding text editor pragmas shortly after the shabang line.

A common example would be:

#!/usr/bin/env cbmbasic
; vim: ts=4
{BASIC source code begins}

The petcat tokenizer that comes with VICE has this feature.