v0.21.0 (WARNING: ALPHA SOFTWARE)

This is a breaking release that updates some components of the SDK and its native modules.

In particular:

• Global pool shares have been removed from the staking logic
• NewBaseApp now takes in option functions to set configurable parameters
• NewAccountMapper now takes a constructor function instead of a prototype
• The --trace-store option has been added to gaiad, which logs all store operations to a file
• IAVL tree pruning is now configurable and enabled by default

See the changelog for complete details:

https://github.com/cosmos/cosmos-sdk/blob/v0.21.0/CHANGELOG.md#0210