fix the table layout of environment variables

Fixed a link

Sending rich pushes and passing info-kp through me topic

Move some stuff off of Topic.run critical path.

Less blocking on the Topic.run critical path.
Move message serialization to the Session's writeLoop.
Allow batch sending of messages to the Session in order
to avoid sending messages to the Sessions' writeLoop
one by one (and thus incur synchronization costs).

Support for drafty push notifications

Support for forwarding {info} to topic-offline users on "me"

Detach sessions immediatelly in topic broadcast logic.

Presently, session attached to a topic that fail to handle a broadcast
(queueOut() returns false) are detached from the topic by
sending a leave request to the topic's unreg channel.

This (a) incurs using a synchronization primitive and (b) may result
in dropped leave requests (if the unreg queue becomes full).

Change the logic to detach all "bad" sessions immediately, without
routing the leave request via the unreg channel.

Roll back to using goroutine pool from gorountine per master topic.

For ease of debugging.

The existing logic using reflect.Select turns out to be quite pricey
in terms of both cpu and memory.

Split logs into info, warning, errors.