Make the documentation versionable using mike

[smileisak]

What this PR does / why we need it:

Adds mike to be able to version the documentation.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

fixes #20

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• All new and existing tests passed.

Does my pull request need a release note?

Any user-visible or operator-visible change qualifies for a release note. This could be a:

• CLI change
• API change
• UI change
• configuration schema change
• behavioral change
• change in non-functional attributes such as efficiency or availability, availability of a new platform
• a warning about a deprecation
• fix of a previous Known Issue
• fix of a vulnerability (CVE)

No release notes are required for changes to the following:

• Tests
• Build infrastructure
• Fixes for unreleased bugs

For more tips on writing good release notes, check out the Release Notes Handbook

Make the documentation versionable using mike