Add support for CKAN 2.10

[avdata99]

Related to CKAN#6787

This PR

• Adds Python 3 compatibility
• Add CKAN 2.9 and 2.10 compatibility
• Remove Travis
• Adds GitHub actions for new tests

Requires archiver and report PRs to be merged

[Zharktas]

QA has not been migrated to 2.9 yet, so it is a larger effort than just adding 2.10 to workflows.