Add capability to concat two FileContainers

[veni-vidi-vici-dormivi]

Very simple method to concatenate two FileContainers together by concatenating there DataFrames.
Closes #94

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.68%. Comparing base (c17e2fd) to head (d3422f3).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   99.67%   99.68%           
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  Files           5        5           
  Lines         308      317    +9     
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+ Hits          307      316    +9     
  Misses          1        1           

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[mathause]

Nice! Do we worry about duplicates?

[veni-vidi-vici-dormivi]

Do we worry about duplicates?

Good question, we could add an option remove_duplicates=True ?

[mathause]

Good idea, with True as default

[mathause]

or maybe drop_duplicates check what pandas does

[veni-vidi-vici-dormivi]

In pd.concat they use verify_integrity and if there are duplicates, they raise a ValueError... not too happy with that tbh.

[veni-vidi-vici-dormivi]

But there is a pandas dataframe drop_duplicates method so that's certainly the better name.

[mathause]

Great!