Allow arguments for "nimrod run"

New try. This time tested with this `foo.nim`:
```nimrod
import os
echo paramStr(0)
echo commandLineParams()
```
Output for `nimrod run --verbosity:0 foo`:
```
foo
@[]
```
Output for `nimrod run --verbosity:0 foo HelloWorld foo bar foobar`:
```
foo                                                      
@[HelloWorld, foo, bar, foobar]
```