0.6.0-alpha

The release is almost entirely is about bugfixes. Tests are fixed to support Clojure 1.10.

Fixes

• fix selective-receive! flushing all the messages in the message queue when the timeout is 0
• fix :DOWN message appearing in the mailbox after a successful call was finished by stopping the gen-server
• spawning a process with an already registered name fails (throws a special exception) with the reason [:already-registered pid]
• slight performance improvement in process/exit fn
• fix a race condition in spawning a process with linking - If the parent process has got an exit signal before the linking is finished, the spawned process remained alive