Changelog for hedis-0.6.8

# Changelog for Hedis ## 0.6.4 * New connection option to automatically SELECT a database. ## 0.5 -> 0.6 * Changed return type of HDEL from Bool to Integer. * Some documentation updates. ## 0.5 -> 0.5.1 * New commands: DUMP, RESTORE, BITOP, BITCOUNT. * Removed the dependency on stm. * Improved performance of Queued in long transactions. * Minor documentation updates. ## 0.4.1 -> 0.5 * Added new Redis 2.6 commands, including Lua scripting support. * A transaction context is now created by using the 'multiExec' function. The functions 'multi', 'exec' and 'discard' are no longer available individually. * Inside of a transaction, commands return their results wrapped in a composable /future/, called 'Queued'. * The 'getType' command (the Redis TYPE command) now has a custom return type 'RedisType'. * Minor improvements and fixes to the documentation. ## 0.3.2 -> 0.4.1 * The following commands got a 'Maybe' added to their return type, to properly handle Redis returning `nil`-replies: `brpoplpush`, `lindex`, `lpop`, `objectEncoding`, `randomkey`, `rpop`, `rpoplpush`, `spop`, `srandmember`, `zrank`, `zrevrank`, `zscore`. * Updated dependencies on `bytestring-lexing` and `stm`. * Minor improvements and fixes to the documentation.