Add bare files support + merge constants and functions to structure overview

[TomasVotruba]

Overview with classes and functions does not make sense, as now there are also triats, functions, global constants, enums etc. To keep data readable, class constant and global constants are now moved to structure overview :+1:

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    "lengths": {
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        "method_average": 3.9
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        "global_constants": 35
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}