* Improves STIX2 support and testing
* Adds documentation on STIX2 support in MVT
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Co-authored-by: Donncha Ó Cearbhaill <donncha.ocearbhaill@amnesty.org>
Not every system uses 'utf-8' as a default encoding for opening files in Python.
Before you say that there must be a way to set default encoding in one line, no, there is not. At least, I didn't found a way to do this.