Improved compilation error output

Currently CoffeeScript compilation errors are outputted like this:
```
>> SyntaxError: unmatched }
>> In file: main.coffee
>> On line: 15
```
I added logging of the erroneous line and an arrow pointing to the offending character just like the CoffeeScript command line compiler does
```
>> SyntaxError: unmatched }
>> In file: main.coffee
>> On line: 15
>> foo =  }
>>        ^
```