8813a63ec9 internals: Bump version to 0.2.0 (Tobin C. Harding)
Pull request description:
In preparation for release bump the version and add a changelog entry. Includes updating the dependency in `bitcoin` and `hashes`.
ACKs for top commit:
apoelstra:
ACK 8813a63ec9
sanket1729:
utACK 8813a63ec9
Tree-SHA512: a9bd9d4d69cba21329f3f63a9948afe566bb97c8c65f5d46c329a696a814e9eb31372d378de1ecf0f43f0cb42f11d53dc51bc467223b34629e61315d48b39a29