Add builtin (chat) macro command

[xmycroftx]

example usage: macro say this will cast blink and sleep 10 seconds;cast blink; sleep 10000

Explanation: Using update tick, we create a clock reference and compare, running macro parsing/execution in a recursive queue draining fashion.

loops are invoked similarly: macro emote blinks;cast blink;sleep 10000;loop

Loop execution is stopped with a macro stop command, but otherwise will continue until the client is closed.

the other subcommand "sleep N" is a "best try" sleep at milisecond precision -- really it's at the precision of the client's TPS/main loop

[xmycroftx]

@cyberjunk Any chance on this one?