espalarm Code

Provide a boot message with timestamp over MQTT.
Change the Peers::Report() method to return a success indicator, currently not really used yet.

More time info to help figure out why image transfer times are 2ms at the server but range between 600ms and 9s (and more) on the client.

Interpret the node list returned after announcement. If the reply of some node doesn't arrive, then its peers will tell us about it : including node name, IP address, and if it is the weather node.

Fix bugs in button handling

More timeout configurability.
Add a node list to the node discovery reply. Example of such a new reply :
{"acknowledge":"node","oled":true,"alarm":"night","nodes":{"node.0":{"name":"prototype","ip":"1.1.1.1","weather":true}}}
This can lead to faster node discovery, especially the weather node.

Add configurable update timeout (partially for now)

Remove dead code, add comment

LoadGif : #if away some debug code.
Oled : display transparent backgrounds in the weather icon properly.

Slightly better debug text

Add a GetForegroundColour() method as well, and use it.