Merge branch 'issue-361'

update schema to match paper. second pass at ga4gh#324.

Closes ga4gh#282: Merge pull request ga4gh#283 from ga4gh/issue-282

ga4gh#282: VariationSet in VRS Python

no removal until v2

update future plans

Updated changelog for 1.2

Merge branch 'stayin-alive' into main

Merge pull request ga4gh#241 from ga4gh/1.1.2

Patch 1.1.2 - Update ChromosomeLocation Prefix

Merge pull request ga4gh#232 from ga4gh/cytoband-interval

updated release hierarchy and versioning note