Attempt to write panics to file instead of just console.

[tehsmeely]

Not enabled in release

Attempt, on panic, to write the PanicInfo to a local file called panic.txt Panics previously would presumably be written to the simulator console but lost forever

Part of adding this i discovered the real final panic was due to abort_with_addr complaining about using a non 0x04 aligned address. Further to this i'm not really sure what abort_with_addr is meant to do, but it doesn't hurt ...