lib: Pretty-print PanicInfo

[har7an]

instead of relying solely on the Debug trait for printing. Also add
some more space to the output, so the Panic is easily recognized between
application text and the backtrace.

Currently, accessing the panic message is an unstable feature in core, see this tracking issue: rust-lang/rust#66745

So unless this lands, the current debug print actually contains more useful information than this PR...

[har7an]

@bjoernQ I learned another trick yesterday, apparently "{:#?}" pretty-prints sturcts in rust, so the output of this PR now looks like this:

======================================
Self-built SX128x example code, no-std
Features:
  - UART


!! A panic occured in 'src/main.rs', at line 77, column 5

PanicInfo {
    payload: Any { .. },
    message: Some(
        Hallo,
    ),
    location: Location {
        file: "src/main.rs",
        line: 77,
        col: 5,
    },
    can_unwind: true,
}

Backtrace:

0x400d495e [sx128x_demo::__xtensa_lx_rt_main:/var/home/ahartmann/repos/mt/playground/sx128x-demo/src/main.rs:77]
0x400d752c [Reset:/usr/local/share/cargo/registry/src/github.com-1ecc6299db9ec823/xtensa-lx-rt-0.13.0/src/lib.rs:77]
0x400d5a41 [ESP32Reset:/usr/local/share/cargo/git/checkouts/esp-hal-33cf057932915da5/d1a2b98/esp32-hal/src/lib.rs:77]

What do you think about it?

[bjoernQ]

@bjoernQ I learned another trick yesterday, apparently "{:#?}" pretty-prints sturcts in rust, so the output of this PR now looks like this:

======================================
Self-built SX128x example code, no-std
Features:
  - UART


!! A panic occured in 'src/main.rs', at line 77, column 5

PanicInfo {
    payload: Any { .. },
    message: Some(
        Hallo,
    ),
    location: Location {
        file: "src/main.rs",
        line: 77,
        col: 5,
    },
    can_unwind: true,
}

Backtrace:

0x400d495e [sx128x_demo::__xtensa_lx_rt_main:/var/home/ahartmann/repos/mt/playground/sx128x-demo/src/main.rs:77]
0x400d752c [Reset:/usr/local/share/cargo/registry/src/github.com-1ecc6299db9ec823/xtensa-lx-rt-0.13.0/src/lib.rs:77]
0x400d5a41 [ESP32Reset:/usr/local/share/cargo/git/checkouts/esp-hal-33cf057932915da5/d1a2b98/esp32-hal/src/lib.rs:77]

What do you think about it?

Good idea!

[bjoernQ]

@jessebraham what do you think?

[MabezDev]

I think this is big improvement :)

[jessebraham]

Very nice, this is much more pleasant to look at 😁 Thanks for the contribution!