Proposal - Improved visual feedback if Radio initialisation fails

[MikesAllotment]

At the moment if the RadioLib init fails it just goes into an infinite hanging wait loop - there is no visual feedback and no messages on the Serial console.

I propose adding:

Option 1) Flashing the onboard LED to indicate Radio init failure. Still go into an infinite loop, but flash S.O.S ... - - - ... pattern to the on-board LED

Option 2) If OLED is present, display message to screen saying "Radio Error". This would require changing the initialisation order so that I2C and OLED is initialised before RadioLib - so more complex changes.

Or both of the above if possible.