New features: Add attribute tags from indicator metadata and support parsing threatconnect metrics/tags

[ag-michael]

Changelog

• Added a parseIndicators function to attempt to parse details of the indicators objects such as confidence,information source and sightings and add them as properties of the attributes. if this approach fails, revert to the previous 'lint roll' approach to grab all observables and just get only the value.
• Update attribute and event tags as well as attribute comment with indicator metadata for the observable/attribute
• Parse threatconnect metrics/tags: https://threatconnect.com/stix-taxii/git
• buildAttribute and attribute parsing functions return the attribute along with the event
• autopep8!
• Tested and working great with alienvault and threatconnect feeds

[lgtm-com[bot]]

This pull request introduces 1 alert when merging 68e3c9b064dedb0b0ca862ee18762dbff70042a1 into 7e8fb42ae8ccc2eeb8b4e5565425c02f20b855af - view on LGTM.com

new alerts:

• 1 for Variable defined multiple times

[lgtm-com[bot]]

This pull request fixes 1 alert when merging ea4aa57442b895353010680f7e1d012b8cc97058 into 7e8fb42ae8ccc2eeb8b4e5565425c02f20b855af - view on LGTM.com

fixed alerts:

• 1 for Unused import

[ag-michael]

Any updates on this PR?

[ag-michael]

No response yet on this PR, any comments/updats?