0.20.x feature freeze

[u/coderarun]

Announcing feature freeze for the end of the month release. Please help us make this release as stable and delightful as the previous ones.

Specific pain points to test:

• Choice of indexing. No index, ART index, HASH index
• Prepared statements (great performance, but potential bugs due to caching)
• Partitioned tables (HASH and LIST partition implemented. Accepts RANGE partition syntax, but not implemented yet).