mrbc with multiple files fails if files don't end or begin with newline

Guessing it has to do with the source being concatenated and mrbc expecting eof in the form of \n.

a.rb:

``` ruby
module A
end
```

b.rb:

``` ruby
module B
end
```

output:

```
$ mrbc -v -o out.mrb b.rb  a.rb
mruby 1.0.0 (2014-01-10) 
a.rb:0:9: syntax error, unexpected keyword_module, expecting $end
NODE_SCOPE:
  NODE_BEGIN:
    NODE_MODULE:
      :B
      body:
        NODE_BEGIN:
```
