Avoid writing unchanged settings
Reset settings between tests
Add IRC server link check and retry after timeout
Fix for #430
Tweak IRC fix #430 to not create multiple clients on extended reconnects
Update Ardunio node slightly in line with latest Windows Serialport patches.
(But there is still a possibly bad underlying problem 
- error not being caught -  in the upstream npm - reported.)
Cross platform fix for Arduino Serial port not there. 
Fix for #428
Remove listener limit on IRC node server connection.

Fixes #431
Wind down excessive logging on IRC node

now only logs connects/reconnects, errors and "raw" input commands
(so you can debug them when you get it wrong)
All other messages appear on the node output anyway.