Pass through extra positional arguments instead of using a flag

[perimosocordiae]

This enables the use of shell globs when passing arguments to an Icarus program, and matches the convention for most interpreted languages.

Before:

$ icarus examples/arguments.ic --program_arguments='foo ba*'
There are 2 program Argument(s):
  foo
  ba*

After:

$ icarus examples/arguments.ic foo ba*
There are 3 program Argument(s):
  foo
  bar
  baz