pngbot.py:IrcMiRCARTBot.clientChannelRejoin{,TimerNext}: added to support delayed rejoin-on-kick logic.
pngbot.py:IrcMiRCARTBot.dispatchJoin(): reset clientChannelRejoin{,TimerNext} on successful (re)join to clientChannel.
pngbot.py:IrcMiRCARTBot.dispatchKick(): set clientChannelRejoin{,TimerNext} on kick from clientChannel to time.time() + 15 (seconds.)
pngbot.py:IrcMiRCARTBot.dispatchTimer(): (re)join clientChannel and set clientChannelRejoin{,TimerNext} to time.time() + 15 (seconds.)
pngbot.py:IrcMiRCARTBot.dispatch(): call readline() w/ timeout delta given clientChannelRejoinTimerNext.
pngbot.py:IrcMiRCARTBot.dispatch(): add status (stdout) messages.
pngbot.py:IrcMiRCARTBot.dispatch(): always use lower-case channel name in status (stdout) messages.
pngbot.py:IrcBot.close(): only close() clientSocket if non-None.
pngbot.py:IrcMiRCARTBot.connect(): correctly zero-initialise clientLastMessage.
pngbot.py:IrcMiRCARTBot.dispatch(): fix imgurResponseHttp.status_code reference.