Make a much more user friendly %connection login

[goatchurchprime]

Not necessary to print the following if it is recognized correct.

Hold the messages back for a second and parse them.

***Connecton broken [Connection timed out]
You may need to reconnectClosing websocket <websocket._core.WebSocket object at 0x7f679c9194e0>
Connecting to Serial /dev/ttyUSB1 baud=115200

 ** Serial connected **

Serial<id=0x7f67996c9780, open=True>(port='/dev/ttyUSB1', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=0.5, xonxoff=False, rtscts=False, dsrdtr=False)

>>> 
>>> 
>>> 
>>> 
raw REPL; CTRL-B to exit
>

[goatchurchprime]

Have made an attempt to put back into paste mode when you do %disconnect

Cannot yet get reliable disconnection and connection on the ESP32 (even when picoweb shows it should be good to serially connect)

[goatchurchprime]

It would be great to change the appearance depending on the connection status.

Closest description is here:
jupyter/notebook#1883

[goatchurchprime]

This is going to involve some form of outputting HTML through the display mechanism in some way
https://github.com/ipython/ipython/blob/master/IPython/core/display.py

and changing the background colour of the kernel status bit using this:
from IPython.core.display import HTML
kk = HTML('<script>document.getElementById("kernel_indicator").style.background="#dfd"</script>')