Nim interact with Windows .NET Frameworks

[Ward]

I believed that you found a compiler bug about generic type. You can report it, 
or use some workarounds:

1\. Use `except` to avoid symbol confliction 
    
    
    import winim/clr except Create
    
    
    Run

2\. Don't use generic type, using type overload instead. 
    
    
    proc fn(fnExcel: string, strSheet: int): int = discard
    proc fn(fnExcel: string, strSheet: string): int = discard
    
    
    Run

3\. Use `invoke` instead of dot operator.