#181 Serialize container tags

[fktn-k]

This PR has added the feature of serializing container tags with related test cases (scalar tags are already supported in #305 ).
Furthermore, the format with which the serialization feature complies are added to the documentation for the basic_node::serialize function.

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[github-actions]

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[coveralls]

Pull Request Test Coverage Report for Build 8763786442

Details

• 8 of 8 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 8763018124:	0.0%
Covered Lines:	3502
Relevant Lines:	3502

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