include_file!() must show the full path and its kind in case of error

[teh-cmc]

We've been chasing a nasty build issue with @jleibs and towards the end had to deal with this error:

thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: No such file or directory (os error 2)', crates/re_renderer/src/renderer/mesh_renderer.rs:286:25
stack backtrace:
   0: rust_begin_unwind
             at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:575:5
   1: core::panicking::panic_fmt
             at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/panicking.rs:64:14
   2: core::result::unwrap_failed
             at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/result.rs:1791:5
   3: core::result::Result<T,E>::unwrap
[...]

which isn't too useful and had us look in all kinds of wrong directions until we realized that this was looking for an actual physical path, meaning this was mistakenly building in debug mode... something that should have been obvious by looking at the error.

include_file!() must indicate the full path and whether its virtual or physical when failing.