Pyaioredis

- Dropped following Redis methods -- `Redis.multi()`,
`Redis.exec()`, `Redis.discard()`
- `Redis.multi_exec` hack'ish property removed
- `Redis.multi_exec()` method added
- High-level commands implemented:

- generic commands (tests)
- transactions commands (api stabilization).

- Backward incompatibilities:

- Following sorted set commands' API changed:

`zcount`, `zrangebyscore`, `zremrangebyscore`, `zrevrangebyscore`
- set string command' API changed

- RedisConnection.execute refactored to support commands pipelining
(see 33)
- Several fixes
- WIP on transactions and commands interface
- High-level commands implemented and tested:

- hash commands
- hyperloglog commands
- set commands
- scripting commands
- string commands
- list commands

- `create_connection`, `create_pool`, `create_redis` functions updated: db and password
arguments made keyword-only
(see 26)
- Fixed transaction handling
(see 32)
- Response decoding
(see 16)

- Transactions support (in connection, high-level commands have some issues)
- Docs & tests updated.

- Initial release
- RedisConnection implemented
- RedisPool implemented
- Docs for RedisConnection & RedisPool
- WIP on high-level API.