Nim : Style insensitivity , snake_case , camelCase

[xflywind]

Also consider using `styleCheck:usages` for big projects, the Nim compiler 
itself already uses more stricter style check: `--styleCheck:error` which 
enforces nep1.
    
    
    The style checking of the compiler now supports a `--styleCheck:usages` 
switch. This switch
    enforces that every symbol is written as it was declared, not enforcing
    the official Nim style guide. To be enabled, this has to be combined either
    with `--styleCheck:error` or `--styleCheck:hint`.
    
    
    Run